diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PythonClientExperimentalCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PythonClientExperimentalCodegen.java
index 5b7138c0686c..384960012385 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PythonClientExperimentalCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PythonClientExperimentalCodegen.java
@@ -97,6 +97,9 @@ public PythonClientExperimentalCodegen() {
         apiDocTemplateFiles.remove("api_doc.mustache");
         apiDocTemplateFiles.put("python-experimental/api_doc.mustache", ".md");
 
+        apiTestTemplateFiles.remove("api_test.mustache", ".py");
+        apiTestTemplateFiles.put("python-experimental/api_test.mustache", ".py");
+
         modelDocTemplateFiles.remove("model_doc.mustache");
         modelDocTemplateFiles.put("python-experimental/model_doc.mustache", ".md");
 
@@ -123,6 +126,7 @@ public void processOpts() {
         this.setLegacyDiscriminatorBehavior(false);
 
         super.processOpts();
+        modelPackage = packageName + "." + "model";
 
         supportingFiles.remove(new SupportingFile("api_client.mustache", packagePath(), "api_client.py"));
         supportingFiles.add(new SupportingFile("python-experimental/api_client.mustache", packagePath(), "api_client.py"));
@@ -130,11 +134,14 @@ public void processOpts() {
         supportingFiles.add(new SupportingFile("python-experimental/model_utils.mustache", packagePath(), "model_utils.py"));
 
         supportingFiles.remove(new SupportingFile("__init__model.mustache", packagePath() + File.separatorChar + "models", "__init__.py"));
-        supportingFiles.add(new SupportingFile("python-experimental/__init__model.mustache", packagePath() + File.separatorChar + "models", "__init__.py"));
+        supportingFiles.add(new SupportingFile("python-experimental/__init__model.mustache", packagePath() + File.separatorChar + "model", "__init__.py"));
 
         supportingFiles.remove(new SupportingFile("__init__package.mustache", packagePath(), "__init__.py"));
         supportingFiles.add(new SupportingFile("python-experimental/__init__package.mustache", packagePath(), "__init__.py"));
 
+        // add the models and apis folders
+        supportingFiles.add(new SupportingFile("python-experimental/__init__models.mustache", packagePath() + File.separatorChar + "models", "__init__.py"));
+        supportingFiles.add(new SupportingFile("python-experimental/__init__apis.mustache", packagePath() + File.separatorChar + "apis", "__init__.py"));
 
         // Generate the 'signing.py' module, but only if the 'HTTP signature' security scheme is specified in the OAS.
         Map<String, SecurityScheme> securitySchemeMap = openAPI != null ?
@@ -518,9 +525,9 @@ public CodegenParameter fromRequestBody(RequestBody body, Set<String> imports, S
             // set the example value
             if (modelProp.isEnum) {
                 String value = modelProp._enum.get(0).toString();
-                result.example = this.packageName + "." + result.baseType + "(" + toEnumValue(value, simpleDataType) + ")";
+                result.example = result.dataType + "(" + toEnumValue(value, simpleDataType) + ")";
             } else {
-                result.example = this.packageName + "." + result.baseType + "(" + result.example + ")";
+                result.example = result.dataType + "(" + result.example + ")";
             }
         } else if (!result.isPrimitiveType) {
             // fix the baseType for the api docs so the .md link to the class's documentation file is correct
@@ -1064,7 +1071,7 @@ public void setParameterExampleValue(CodegenParameter p) {
             example = "'" + escapeText(example) + "'";
         } else if (!languageSpecificPrimitives.contains(type)) {
             // type is a model class, e.g. user.User
-            example = this.packageName + "." + getPythonClassName(type) + "()";
+            example = type + "()";
         } else {
             LOGGER.warn("Type " + type + " not handled properly in setParameterExampleValue");
         }
diff --git a/modules/openapi-generator/src/main/resources/python/python-experimental/README_common.mustache b/modules/openapi-generator/src/main/resources/python/python-experimental/README_common.mustache
index 7d9811fdfb85..0f6dcb41d6f6 100644
--- a/modules/openapi-generator/src/main/resources/python/python-experimental/README_common.mustache
+++ b/modules/openapi-generator/src/main/resources/python/python-experimental/README_common.mustache
@@ -4,13 +4,22 @@ from __future__ import print_function
 import time
 import {{{packageName}}}
 from pprint import pprint
-{{#apiInfo}}{{#apis}}{{#-first}}{{#operations}}{{#operation}}{{#-first}}
+{{#apiInfo}}
+{{#apis}}
+{{#-first}}
+from {{apiPackage}} import {{classVarName}}
+{{#imports}}
+{{{import}}}
+{{/imports}}
+{{#operations}}
+{{#operation}}
+{{#-first}}
 {{> python_doc_auth_partial}}
 
 # Enter a context with an instance of the API client
 with {{{packageName}}}.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = {{{packageName}}}.{{{classname}}}(api_client)
+    api_instance = {{classVarName}}.{{{classname}}}(api_client)
     {{#allParams}}{{paramName}} = {{{example}}} # {{{dataType}}} | {{{description}}}{{^required}} (optional){{/required}}{{#defaultValue}} (default to {{{.}}}){{/defaultValue}}
     {{/allParams}}
 
@@ -20,7 +29,12 @@ with {{{packageName}}}.ApiClient(configuration) as api_client:
         pprint(api_response){{/returnType}}
     except {{{packageName}}}.ApiException as e:
         print("Exception when calling {{classname}}->{{operationId}}: %s\n" % e)
-    {{/-first}}{{/operation}}{{/operations}}{{/-first}}{{/apis}}{{/apiInfo}}
+{{/-first}}
+{{/operation}}
+{{/operations}}
+{{/-first}}
+{{/apis}}
+{{/apiInfo}}
 ```
 
 ## Documentation for API Endpoints
@@ -77,3 +91,22 @@ Class | Method | HTTP request | Description
 
 {{#apiInfo}}{{#apis}}{{^hasMore}}{{infoEmail}}
 {{/hasMore}}{{/apis}}{{/apiInfo}}
+
+## Notes for Large OpenAPI documents
+If the OpenAPI document is large, imports in {{{packageName}}}.apis and {{{packageName}}}.models may fail with a
+RecursionError indicating the maximum recursion limit has been exceeded. In that case, there are a couple of solutions:
+
+Solution 1:
+Use specific imports for apis and models like:
+- `from {{{packageName}}}.api.default_api import DefaultApi`
+- `from {{{packageName}}}.model.pet import Pet`
+
+Solution 1:
+Before importing the package, adjust the maximum recursion limit as shown below:
+```
+import sys
+sys.setrecursionlimit(1500)
+import {{{packageName}}}
+from {{{packageName}}}.apis import *
+from {{{packageName}}}.models import *
+```
diff --git a/modules/openapi-generator/src/main/resources/python/python-experimental/__init__api.mustache b/modules/openapi-generator/src/main/resources/python/python-experimental/__init__api.mustache
new file mode 100644
index 000000000000..d37ee6c78b29
--- /dev/null
+++ b/modules/openapi-generator/src/main/resources/python/python-experimental/__init__api.mustache
@@ -0,0 +1,3 @@
+# do not import all apis into this module because that uses a lot of memory and stack frames
+# if you need the ability to import all models from one package, import them with
+# from {{packageName}.apis import DefaultApi, PetApi
\ No newline at end of file
diff --git a/modules/openapi-generator/src/main/resources/python/python-experimental/__init__apis.mustache b/modules/openapi-generator/src/main/resources/python/python-experimental/__init__apis.mustache
new file mode 100644
index 000000000000..b5b7065e1ed2
--- /dev/null
+++ b/modules/openapi-generator/src/main/resources/python/python-experimental/__init__apis.mustache
@@ -0,0 +1,19 @@
+# coding: utf-8
+
+# flake8: noqa
+
+# import all apis into this package
+# if you have many ampis here with many many models used in each api this may
+# raise a RecursionError
+# to avoid this, import only the api that you directly need like:
+# from {{packagename}}.api.pet_api import PetApi
+# or import this package, but before doing it, use:
+# import sys
+# sys.setrecursionlimit(n)
+
+# import apis into api package
+{{#apiInfo}}
+{{#apis}}
+from {{apiPackage}}.{{classVarName}} import {{classname}}
+{{/apis}}
+{{/apiInfo}}
\ No newline at end of file
diff --git a/modules/openapi-generator/src/main/resources/python/python-experimental/__init__model.mustache b/modules/openapi-generator/src/main/resources/python/python-experimental/__init__model.mustache
index ca86cb8a6249..cfe32b784926 100644
--- a/modules/openapi-generator/src/main/resources/python/python-experimental/__init__model.mustache
+++ b/modules/openapi-generator/src/main/resources/python/python-experimental/__init__model.mustache
@@ -1,7 +1,5 @@
-# coding: utf-8
-
-# flake8: noqa
-{{>partial_header}}
-
 # we can not import model classes here because that would create a circular
 # reference which would not work in python2
+# do not import all models into this module because that uses a lot of memory and stack frames
+# if you need the ability to import all models from one package, import them with
+# from {{packageName}.models import ModelA, ModelB
diff --git a/modules/openapi-generator/src/main/resources/python/python-experimental/__init__models.mustache b/modules/openapi-generator/src/main/resources/python/python-experimental/__init__models.mustache
new file mode 100644
index 000000000000..abe69dc03504
--- /dev/null
+++ b/modules/openapi-generator/src/main/resources/python/python-experimental/__init__models.mustache
@@ -0,0 +1,18 @@
+# coding: utf-8
+
+# flake8: noqa
+
+# import all models into this package
+# if you have many models here with many references from one model to another this may
+# raise a RecursionError
+# to avoid this, import only the models that you directly need like:
+# from from {{modelPackage}}.pet import Pet
+# or import this package, but before doing it, use:
+# import sys
+# sys.setrecursionlimit(n)
+
+{{#models}}
+{{#model}}
+from {{modelPackage}}.{{classFilename}} import {{unescapedDescription}}
+{{/model}}
+{{/models}}
diff --git a/modules/openapi-generator/src/main/resources/python/python-experimental/__init__package.mustache b/modules/openapi-generator/src/main/resources/python/python-experimental/__init__package.mustache
index 1d74d016ab47..a949d5085067 100644
--- a/modules/openapi-generator/src/main/resources/python/python-experimental/__init__package.mustache
+++ b/modules/openapi-generator/src/main/resources/python/python-experimental/__init__package.mustache
@@ -8,13 +8,6 @@ from __future__ import absolute_import
 
 __version__ = "{{packageVersion}}"
 
-# import apis into sdk package
-{{#apiInfo}}
-{{#apis}}
-from {{apiPackage}}.{{classVarName}} import {{classname}}
-{{/apis}}
-{{/apiInfo}}
-
 # import ApiClient
 from {{packageName}}.api_client import ApiClient
 
@@ -26,14 +19,8 @@ from {{packageName}}.signing import HttpSigningConfiguration
 
 # import exceptions
 from {{packageName}}.exceptions import OpenApiException
+from {{packageName}}.exceptions import ApiAttributeError
 from {{packageName}}.exceptions import ApiTypeError
 from {{packageName}}.exceptions import ApiValueError
 from {{packageName}}.exceptions import ApiKeyError
-from {{packageName}}.exceptions import ApiException
-
-# import models into sdk package
-{{#models}}
-{{#model}}
-from {{modelPackage}}.{{classFilename}} import {{unescapedDescription}}
-{{/model}}
-{{/models}}
+from {{packageName}}.exceptions import ApiException
\ No newline at end of file
diff --git a/modules/openapi-generator/src/main/resources/python/python-experimental/api_doc_example.mustache b/modules/openapi-generator/src/main/resources/python/python-experimental/api_doc_example.mustache
index ae7b8a697970..23cf85e9dffa 100644
--- a/modules/openapi-generator/src/main/resources/python/python-experimental/api_doc_example.mustache
+++ b/modules/openapi-generator/src/main/resources/python/python-experimental/api_doc_example.mustache
@@ -2,6 +2,10 @@
 from __future__ import print_function
 import time
 import {{{packageName}}}
+from {{apiPackage}} import {{classVarName}}
+{{#imports}}
+{{{.}}}
+{{/imports}}
 from pprint import pprint
 {{> python_doc_auth_partial}}
 # Enter a context with an instance of the API client
@@ -12,7 +16,7 @@ with {{{packageName}}}.ApiClient(configuration) as api_client:
 with {{{packageName}}}.ApiClient() as api_client:
 {{/hasAuthMethods}}
     # Create an instance of the API class
-    api_instance = {{{packageName}}}.{{{classname}}}(api_client)
+    api_instance = {{classVarName}}.{{{classname}}}(api_client)
     {{#requiredParams}}{{^defaultValue}}{{paramName}} = {{{example}}} # {{{dataType}}} | {{{description}}}
     {{/defaultValue}}{{/requiredParams}}{{#optionalParams}}{{paramName}} = {{{example}}} # {{{dataType}}} | {{{description}}}{{^required}} (optional){{/required}}{{#defaultValue}} if omitted the server will use the default value of {{{defaultValue}}}{{/defaultValue}}
     {{/optionalParams}}
diff --git a/modules/openapi-generator/src/main/resources/python/python-experimental/api_test.mustache b/modules/openapi-generator/src/main/resources/python/python-experimental/api_test.mustache
new file mode 100644
index 000000000000..e04b32f96edb
--- /dev/null
+++ b/modules/openapi-generator/src/main/resources/python/python-experimental/api_test.mustache
@@ -0,0 +1,36 @@
+# coding: utf-8
+
+{{>partial_header}}
+
+from __future__ import absolute_import
+
+import unittest
+
+import {{packageName}}
+from {{apiPackage}}.{{classVarName}} import {{classname}}  # noqa: E501
+
+
+class {{#operations}}Test{{classname}}(unittest.TestCase):
+    """{{classname}} unit test stubs"""
+
+    def setUp(self):
+        self.api = {{classname}}()  # noqa: E501
+
+    def tearDown(self):
+        pass
+
+   {{#operation}}
+    def test_{{operationId}}(self):
+        """Test case for {{{operationId}}}
+
+{{#summary}}
+        {{{summary}}}  # noqa: E501
+{{/summary}}
+        """
+        pass
+
+   {{/operation}}
+{{/operations}}
+
+if __name__ == '__main__':
+    unittest.main()
diff --git a/modules/openapi-generator/src/main/resources/python/python-experimental/model_test.mustache b/modules/openapi-generator/src/main/resources/python/python-experimental/model_test.mustache
index 4fd1263b5f28..5b9a91d2d073 100644
--- a/modules/openapi-generator/src/main/resources/python/python-experimental/model_test.mustache
+++ b/modules/openapi-generator/src/main/resources/python/python-experimental/model_test.mustache
@@ -3,12 +3,16 @@
 {{>partial_header}}
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
+import {{packageName}}
 {{#models}}
 {{#model}}
-import {{packageName}}
+{{#imports}}
+{{{.}}}
+{{/imports}}
+from {{modelPackage}}.{{classFilename}} import {{unescapedDescription}}
 
 
 class Test{{unescapedDescription}}(unittest.TestCase):
@@ -23,7 +27,7 @@ class Test{{unescapedDescription}}(unittest.TestCase):
     def test{{unescapedDescription}}(self):
         """Test {{unescapedDescription}}"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = {{packageName}}.{{unescapedDescription}}()  # noqa: E501
+        # model = {{unescapedDescription}}()  # noqa: E501
         pass
 
 {{/model}}
diff --git a/samples/client/petstore/python-experimental/.openapi-generator/FILES b/samples/client/petstore/python-experimental/.openapi-generator/FILES
index e855d6b1ef4e..d282130ffbc0 100644
--- a/samples/client/petstore/python-experimental/.openapi-generator/FILES
+++ b/samples/client/petstore/python-experimental/.openapi-generator/FILES
@@ -80,72 +80,74 @@ petstore_api/api/pet_api.py
 petstore_api/api/store_api.py
 petstore_api/api/user_api.py
 petstore_api/api_client.py
+petstore_api/apis/__init__.py
 petstore_api/configuration.py
 petstore_api/exceptions.py
+petstore_api/model/__init__.py
+petstore_api/model/additional_properties_any_type.py
+petstore_api/model/additional_properties_array.py
+petstore_api/model/additional_properties_boolean.py
+petstore_api/model/additional_properties_class.py
+petstore_api/model/additional_properties_integer.py
+petstore_api/model/additional_properties_number.py
+petstore_api/model/additional_properties_object.py
+petstore_api/model/additional_properties_string.py
+petstore_api/model/animal.py
+petstore_api/model/api_response.py
+petstore_api/model/array_of_array_of_number_only.py
+petstore_api/model/array_of_number_only.py
+petstore_api/model/array_test.py
+petstore_api/model/capitalization.py
+petstore_api/model/cat.py
+petstore_api/model/cat_all_of.py
+petstore_api/model/category.py
+petstore_api/model/child.py
+petstore_api/model/child_all_of.py
+petstore_api/model/child_cat.py
+petstore_api/model/child_cat_all_of.py
+petstore_api/model/child_dog.py
+petstore_api/model/child_dog_all_of.py
+petstore_api/model/child_lizard.py
+petstore_api/model/child_lizard_all_of.py
+petstore_api/model/class_model.py
+petstore_api/model/client.py
+petstore_api/model/dog.py
+petstore_api/model/dog_all_of.py
+petstore_api/model/enum_arrays.py
+petstore_api/model/enum_class.py
+petstore_api/model/enum_test.py
+petstore_api/model/file.py
+petstore_api/model/file_schema_test_class.py
+petstore_api/model/format_test.py
+petstore_api/model/grandparent.py
+petstore_api/model/grandparent_animal.py
+petstore_api/model/has_only_read_only.py
+petstore_api/model/list.py
+petstore_api/model/map_test.py
+petstore_api/model/mixed_properties_and_additional_properties_class.py
+petstore_api/model/model200_response.py
+petstore_api/model/model_return.py
+petstore_api/model/name.py
+petstore_api/model/number_only.py
+petstore_api/model/order.py
+petstore_api/model/outer_composite.py
+petstore_api/model/outer_enum.py
+petstore_api/model/outer_number.py
+petstore_api/model/parent.py
+petstore_api/model/parent_all_of.py
+petstore_api/model/parent_pet.py
+petstore_api/model/pet.py
+petstore_api/model/player.py
+petstore_api/model/read_only_first.py
+petstore_api/model/special_model_name.py
+petstore_api/model/string_boolean_map.py
+petstore_api/model/tag.py
+petstore_api/model/type_holder_default.py
+petstore_api/model/type_holder_example.py
+petstore_api/model/user.py
+petstore_api/model/xml_item.py
 petstore_api/model_utils.py
 petstore_api/models/__init__.py
-petstore_api/models/additional_properties_any_type.py
-petstore_api/models/additional_properties_array.py
-petstore_api/models/additional_properties_boolean.py
-petstore_api/models/additional_properties_class.py
-petstore_api/models/additional_properties_integer.py
-petstore_api/models/additional_properties_number.py
-petstore_api/models/additional_properties_object.py
-petstore_api/models/additional_properties_string.py
-petstore_api/models/animal.py
-petstore_api/models/api_response.py
-petstore_api/models/array_of_array_of_number_only.py
-petstore_api/models/array_of_number_only.py
-petstore_api/models/array_test.py
-petstore_api/models/capitalization.py
-petstore_api/models/cat.py
-petstore_api/models/cat_all_of.py
-petstore_api/models/category.py
-petstore_api/models/child.py
-petstore_api/models/child_all_of.py
-petstore_api/models/child_cat.py
-petstore_api/models/child_cat_all_of.py
-petstore_api/models/child_dog.py
-petstore_api/models/child_dog_all_of.py
-petstore_api/models/child_lizard.py
-petstore_api/models/child_lizard_all_of.py
-petstore_api/models/class_model.py
-petstore_api/models/client.py
-petstore_api/models/dog.py
-petstore_api/models/dog_all_of.py
-petstore_api/models/enum_arrays.py
-petstore_api/models/enum_class.py
-petstore_api/models/enum_test.py
-petstore_api/models/file.py
-petstore_api/models/file_schema_test_class.py
-petstore_api/models/format_test.py
-petstore_api/models/grandparent.py
-petstore_api/models/grandparent_animal.py
-petstore_api/models/has_only_read_only.py
-petstore_api/models/list.py
-petstore_api/models/map_test.py
-petstore_api/models/mixed_properties_and_additional_properties_class.py
-petstore_api/models/model200_response.py
-petstore_api/models/model_return.py
-petstore_api/models/name.py
-petstore_api/models/number_only.py
-petstore_api/models/order.py
-petstore_api/models/outer_composite.py
-petstore_api/models/outer_enum.py
-petstore_api/models/outer_number.py
-petstore_api/models/parent.py
-petstore_api/models/parent_all_of.py
-petstore_api/models/parent_pet.py
-petstore_api/models/pet.py
-petstore_api/models/player.py
-petstore_api/models/read_only_first.py
-petstore_api/models/special_model_name.py
-petstore_api/models/string_boolean_map.py
-petstore_api/models/tag.py
-petstore_api/models/type_holder_default.py
-petstore_api/models/type_holder_example.py
-petstore_api/models/user.py
-petstore_api/models/xml_item.py
 petstore_api/rest.py
 requirements.txt
 setup.cfg
diff --git a/samples/client/petstore/python-experimental/README.md b/samples/client/petstore/python-experimental/README.md
index 81b680fa57b3..d6b85d02a55a 100644
--- a/samples/client/petstore/python-experimental/README.md
+++ b/samples/client/petstore/python-experimental/README.md
@@ -50,7 +50,8 @@ from __future__ import print_function
 import time
 import petstore_api
 from pprint import pprint
-
+from petstore_api.api import another_fake_api
+from petstore_api.model import client
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
 configuration = petstore_api.Configuration(
@@ -62,8 +63,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.AnotherFakeApi(api_client)
-    body = petstore_api.Client() # client.Client | client model
+    api_instance = another_fake_api.AnotherFakeApi(api_client)
+    body = client.Client() # client.Client | client model
 
     try:
         # To test special tags
@@ -71,7 +72,6 @@ with petstore_api.ApiClient(configuration) as api_client:
         pprint(api_response)
     except petstore_api.ApiException as e:
         print("Exception when calling AnotherFakeApi->call_123_test_special_tags: %s\n" % e)
-    
 ```
 
 ## Documentation for API Endpoints
@@ -223,3 +223,22 @@ Class | Method | HTTP request | Description
 
 
 
+## Notes for Large OpenAPI documents
+If the OpenAPI document is large, imports in petstore_api.apis and petstore_api.models may fail with a
+RecursionError indicating the maximum recursion limit has been exceeded. In that case, there are a couple of solutions:
+
+Solution 1:
+Use specific imports for apis and models like:
+- `from petstore_api.api.default_api import DefaultApi`
+- `from petstore_api.model.pet import Pet`
+
+Solution 1:
+Before importing the package, adjust the maximum recursion limit as shown below:
+```
+import sys
+sys.setrecursionlimit(1500)
+import petstore_api
+from petstore_api.apis import *
+from petstore_api.models import *
+```
+
diff --git a/samples/client/petstore/python-experimental/docs/AnotherFakeApi.md b/samples/client/petstore/python-experimental/docs/AnotherFakeApi.md
index 83a89addfaee..8b7a61109454 100644
--- a/samples/client/petstore/python-experimental/docs/AnotherFakeApi.md
+++ b/samples/client/petstore/python-experimental/docs/AnotherFakeApi.md
@@ -20,6 +20,8 @@ To test special tags and operation ID starting with number
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import another_fake_api
+from petstore_api.model import client
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -31,8 +33,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.AnotherFakeApi(api_client)
-    body = petstore_api.Client() # client.Client | client model
+    api_instance = another_fake_api.AnotherFakeApi(api_client)
+    body = client.Client() # client.Client | client model
     
     # example passing only required values which don't have defaults set
     try:
diff --git a/samples/client/petstore/python-experimental/docs/FakeApi.md b/samples/client/petstore/python-experimental/docs/FakeApi.md
index de9a3fd1a4fb..7f813d160f77 100644
--- a/samples/client/petstore/python-experimental/docs/FakeApi.md
+++ b/samples/client/petstore/python-experimental/docs/FakeApi.md
@@ -34,6 +34,8 @@ this route creates an XmlItem
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
+from petstore_api.model import xml_item
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -45,8 +47,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
-    xml_item = petstore_api.XmlItem() # xml_item.XmlItem | XmlItem Body
+    api_instance = fake_api.FakeApi(api_client)
+    xml_item = xml_item.XmlItem() # xml_item.XmlItem | XmlItem Body
     
     # example passing only required values which don't have defaults set
     try:
@@ -95,6 +97,7 @@ Test serialization of outer boolean types
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -106,7 +109,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     body = True # bool | Input boolean as post body (optional)
 
     # example passing only required values which don't have defaults set
@@ -157,6 +160,8 @@ Test serialization of object with outer number type
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
+from petstore_api.model import outer_composite
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -168,8 +173,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
-    body = petstore_api.OuterComposite() # outer_composite.OuterComposite | Input composite as post body (optional)
+    api_instance = fake_api.FakeApi(api_client)
+    body = outer_composite.OuterComposite() # outer_composite.OuterComposite | Input composite as post body (optional)
 
     # example passing only required values which don't have defaults set
     # and optional values
@@ -219,6 +224,8 @@ Test serialization of outer enum
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
+from petstore_api.model import outer_enum
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -230,8 +237,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
-    body = petstore_api.OuterEnum("placed") # outer_enum.OuterEnum | Input enum as post body (optional)
+    api_instance = fake_api.FakeApi(api_client)
+    body = outer_enum.OuterEnum("placed") # outer_enum.OuterEnum | Input enum as post body (optional)
 
     # example passing only required values which don't have defaults set
     # and optional values
@@ -281,6 +288,8 @@ Test serialization of outer number types
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
+from petstore_api.model import outer_number
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -292,8 +301,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
-    body = petstore_api.OuterNumber(3.4) # outer_number.OuterNumber | Input number as post body (optional)
+    api_instance = fake_api.FakeApi(api_client)
+    body = outer_number.OuterNumber(3.4) # outer_number.OuterNumber | Input number as post body (optional)
 
     # example passing only required values which don't have defaults set
     # and optional values
@@ -343,6 +352,7 @@ Test serialization of outer string types
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -354,7 +364,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     body = 'body_example' # str | Input string as post body (optional)
 
     # example passing only required values which don't have defaults set
@@ -405,6 +415,8 @@ For this test, the body for this request much reference a schema named `File`.
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
+from petstore_api.model import file_schema_test_class
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -416,8 +428,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
-    body = petstore_api.FileSchemaTestClass() # file_schema_test_class.FileSchemaTestClass | 
+    api_instance = fake_api.FakeApi(api_client)
+    body = file_schema_test_class.FileSchemaTestClass() # file_schema_test_class.FileSchemaTestClass | 
     
     # example passing only required values which don't have defaults set
     try:
@@ -463,6 +475,8 @@ No authorization required
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
+from petstore_api.model import user
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -474,9 +488,9 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     query = 'query_example' # str | 
-    body = petstore_api.User() # user.User | 
+    body = user.User() # user.User | 
     
     # example passing only required values which don't have defaults set
     try:
@@ -525,6 +539,8 @@ To test \"client\" model
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
+from petstore_api.model import client
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -536,8 +552,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
-    body = petstore_api.Client() # client.Client | client model
+    api_instance = fake_api.FakeApi(api_client)
+    body = client.Client() # client.Client | client model
     
     # example passing only required values which don't have defaults set
     try:
@@ -587,6 +603,7 @@ This route has required values with enums of 1
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -598,7 +615,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     
     # example passing only required values which don't have defaults set
     try:
@@ -651,6 +668,7 @@ Fake endpoint for testing various parameters  假端點  偽のエンドポイ
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -672,7 +690,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     number = 3.4 # float | None
     double = 3.4 # float | None
     pattern_without_delimiter = 'pattern_without_delimiter_example' # str | None
@@ -757,6 +775,7 @@ To test enum parameters
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -768,7 +787,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     enum_header_string_array = ['enum_header_string_array_example'] # [str] | Header parameter enum test (string array) (optional)
 enum_header_string = '-efg' # str | Header parameter enum test (string) (optional) if omitted the server will use the default value of '-efg'
 enum_query_string_array = ['enum_query_string_array_example'] # [str] | Query parameter enum test (string array) (optional)
@@ -834,6 +853,7 @@ Fake endpoint to test group parameters (optional)
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -845,7 +865,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     required_string_group = 56 # int | Required String in group parameters
     required_boolean_group = True # bool | Required Boolean in group parameters
     required_int64_group = 56 # int | Required Integer in group parameters
@@ -911,6 +931,7 @@ test inline additionalProperties
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -922,7 +943,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     param = {'key': 'param_example'} # {str: (str,)} | request body
     
     # example passing only required values which don't have defaults set
@@ -970,6 +991,7 @@ test json serialization of form data
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -981,7 +1003,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     param = 'param_example' # str | field1
     param2 = 'param2_example' # str | field2
     
diff --git a/samples/client/petstore/python-experimental/docs/FakeClassnameTags123Api.md b/samples/client/petstore/python-experimental/docs/FakeClassnameTags123Api.md
index c10f9f37e164..6cc246194992 100644
--- a/samples/client/petstore/python-experimental/docs/FakeClassnameTags123Api.md
+++ b/samples/client/petstore/python-experimental/docs/FakeClassnameTags123Api.md
@@ -21,6 +21,8 @@ To test class name in snake case
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_classname_tags_123_api
+from petstore_api.model import client
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -46,8 +48,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeClassnameTags123Api(api_client)
-    body = petstore_api.Client() # client.Client | client model
+    api_instance = fake_classname_tags_123_api.FakeClassnameTags123Api(api_client)
+    body = client.Client() # client.Client | client model
     
     # example passing only required values which don't have defaults set
     try:
diff --git a/samples/client/petstore/python-experimental/docs/PetApi.md b/samples/client/petstore/python-experimental/docs/PetApi.md
index d7192a2dd5f3..20b56372d833 100644
--- a/samples/client/petstore/python-experimental/docs/PetApi.md
+++ b/samples/client/petstore/python-experimental/docs/PetApi.md
@@ -27,6 +27,8 @@ Add a new pet to the store
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
+from petstore_api.model import pet
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -48,8 +50,8 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
-    body = petstore_api.Pet() # pet.Pet | Pet object that needs to be added to the store
+    api_instance = pet_api.PetApi(api_client)
+    body = pet.Pet() # pet.Pet | Pet object that needs to be added to the store
     
     # example passing only required values which don't have defaults set
     try:
@@ -98,6 +100,7 @@ Deletes a pet
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -119,7 +122,7 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
+    api_instance = pet_api.PetApi(api_client)
     pet_id = 56 # int | Pet id to delete
     api_key = 'api_key_example' # str |  (optional)
 
@@ -181,6 +184,8 @@ Multiple status values can be provided with comma separated strings
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
+from petstore_api.model import pet
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -202,7 +207,7 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
+    api_instance = pet_api.PetApi(api_client)
     status = ['status_example'] # [str] | Status values that need to be considered for filter
     
     # example passing only required values which don't have defaults set
@@ -255,6 +260,8 @@ Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
+from petstore_api.model import pet
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -276,7 +283,7 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
+    api_instance = pet_api.PetApi(api_client)
     tags = ['tags_example'] # [str] | Tags to filter by
     
     # example passing only required values which don't have defaults set
@@ -329,6 +336,8 @@ Returns a single pet
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
+from petstore_api.model import pet
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -354,7 +363,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
+    api_instance = pet_api.PetApi(api_client)
     pet_id = 56 # int | ID of pet to return
     
     # example passing only required values which don't have defaults set
@@ -406,6 +415,8 @@ Update an existing pet
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
+from petstore_api.model import pet
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -427,8 +438,8 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
-    body = petstore_api.Pet() # pet.Pet | Pet object that needs to be added to the store
+    api_instance = pet_api.PetApi(api_client)
+    body = pet.Pet() # pet.Pet | Pet object that needs to be added to the store
     
     # example passing only required values which don't have defaults set
     try:
@@ -479,6 +490,7 @@ Updates a pet in the store with form data
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -500,7 +512,7 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
+    api_instance = pet_api.PetApi(api_client)
     pet_id = 56 # int | ID of pet that needs to be updated
     name = 'name_example' # str | Updated name of the pet (optional)
 status = 'status_example' # str | Updated status of the pet (optional)
@@ -561,6 +573,8 @@ uploads an image
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
+from petstore_api.model import api_response
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -582,7 +596,7 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
+    api_instance = pet_api.PetApi(api_client)
     pet_id = 56 # int | ID of pet to update
     additional_metadata = 'additional_metadata_example' # str | Additional data to pass to server (optional)
 file = open('/path/to/file', 'rb') # file_type | file to upload (optional)
@@ -647,6 +661,8 @@ uploads an image (required)
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
+from petstore_api.model import api_response
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -668,7 +684,7 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
+    api_instance = pet_api.PetApi(api_client)
     pet_id = 56 # int | ID of pet to update
     required_file = open('/path/to/file', 'rb') # file_type | file to upload
     additional_metadata = 'additional_metadata_example' # str | Additional data to pass to server (optional)
diff --git a/samples/client/petstore/python-experimental/docs/StoreApi.md b/samples/client/petstore/python-experimental/docs/StoreApi.md
index b4492962d69c..36e72b2ac4f1 100644
--- a/samples/client/petstore/python-experimental/docs/StoreApi.md
+++ b/samples/client/petstore/python-experimental/docs/StoreApi.md
@@ -23,6 +23,7 @@ For valid response try integer IDs with value < 1000. Anything above 1000 or non
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import store_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -34,7 +35,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.StoreApi(api_client)
+    api_instance = store_api.StoreApi(api_client)
     order_id = 'order_id_example' # str | ID of the order that needs to be deleted
     
     # example passing only required values which don't have defaults set
@@ -86,6 +87,7 @@ Returns a map of status codes to quantities
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import store_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -111,7 +113,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.StoreApi(api_client)
+    api_instance = store_api.StoreApi(api_client)
     
     # example, this endpoint has no required or optional parameters
     try:
@@ -158,6 +160,8 @@ For valid response try integer IDs with value <= 5 or > 10. Other values will ge
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import store_api
+from petstore_api.model import order
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -169,7 +173,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.StoreApi(api_client)
+    api_instance = store_api.StoreApi(api_client)
     order_id = 56 # int | ID of pet that needs to be fetched
     
     # example passing only required values which don't have defaults set
@@ -220,6 +224,8 @@ Place an order for a pet
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import store_api
+from petstore_api.model import order
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -231,8 +237,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.StoreApi(api_client)
-    body = petstore_api.Order() # order.Order | order placed for purchasing the pet
+    api_instance = store_api.StoreApi(api_client)
+    body = order.Order() # order.Order | order placed for purchasing the pet
     
     # example passing only required values which don't have defaults set
     try:
diff --git a/samples/client/petstore/python-experimental/docs/UserApi.md b/samples/client/petstore/python-experimental/docs/UserApi.md
index b02b92afbf74..4727961273c1 100644
--- a/samples/client/petstore/python-experimental/docs/UserApi.md
+++ b/samples/client/petstore/python-experimental/docs/UserApi.md
@@ -27,6 +27,8 @@ This can only be done by the logged in user.
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
+from petstore_api.model import user
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -38,8 +40,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
-    body = petstore_api.User() # user.User | Created user object
+    api_instance = user_api.UserApi(api_client)
+    body = user.User() # user.User | Created user object
     
     # example passing only required values which don't have defaults set
     try:
@@ -86,6 +88,8 @@ Creates list of users with given input array
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
+from petstore_api.model import user
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -97,8 +101,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
-    body = [petstore_api.User()] # [user.User] | List of user object
+    api_instance = user_api.UserApi(api_client)
+    body = [user.User()] # [user.User] | List of user object
     
     # example passing only required values which don't have defaults set
     try:
@@ -145,6 +149,8 @@ Creates list of users with given input array
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
+from petstore_api.model import user
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -156,8 +162,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
-    body = [petstore_api.User()] # [user.User] | List of user object
+    api_instance = user_api.UserApi(api_client)
+    body = [user.User()] # [user.User] | List of user object
     
     # example passing only required values which don't have defaults set
     try:
@@ -206,6 +212,7 @@ This can only be done by the logged in user.
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -217,7 +224,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
+    api_instance = user_api.UserApi(api_client)
     username = 'username_example' # str | The name that needs to be deleted
     
     # example passing only required values which don't have defaults set
@@ -266,6 +273,8 @@ Get user by user name
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
+from petstore_api.model import user
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -277,7 +286,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
+    api_instance = user_api.UserApi(api_client)
     username = 'username_example' # str | The name that needs to be fetched. Use user1 for testing.
     
     # example passing only required values which don't have defaults set
@@ -328,6 +337,7 @@ Logs user into the system
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -339,7 +349,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
+    api_instance = user_api.UserApi(api_client)
     username = 'username_example' # str | The user name for login
     password = 'password_example' # str | The password for login in clear text
     
@@ -391,6 +401,7 @@ Logs out current logged in user session
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -402,7 +413,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
+    api_instance = user_api.UserApi(api_client)
     
     # example, this endpoint has no required or optional parameters
     try:
@@ -448,6 +459,8 @@ This can only be done by the logged in user.
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
+from petstore_api.model import user
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -459,9 +472,9 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
+    api_instance = user_api.UserApi(api_client)
     username = 'username_example' # str | name that need to be deleted
-    body = petstore_api.User() # user.User | Updated user object
+    body = user.User() # user.User | Updated user object
     
     # example passing only required values which don't have defaults set
     try:
diff --git a/samples/client/petstore/python-experimental/petstore_api/__init__.py b/samples/client/petstore/python-experimental/petstore_api/__init__.py
index 445bf2409aee..4af4353187f6 100644
--- a/samples/client/petstore/python-experimental/petstore_api/__init__.py
+++ b/samples/client/petstore/python-experimental/petstore_api/__init__.py
@@ -16,14 +16,6 @@
 
 __version__ = "1.0.0"
 
-# import apis into sdk package
-from petstore_api.api.another_fake_api import AnotherFakeApi
-from petstore_api.api.fake_api import FakeApi
-from petstore_api.api.fake_classname_tags_123_api import FakeClassnameTags123Api
-from petstore_api.api.pet_api import PetApi
-from petstore_api.api.store_api import StoreApi
-from petstore_api.api.user_api import UserApi
-
 # import ApiClient
 from petstore_api.api_client import ApiClient
 
@@ -32,71 +24,8 @@
 
 # import exceptions
 from petstore_api.exceptions import OpenApiException
+from petstore_api.exceptions import ApiAttributeError
 from petstore_api.exceptions import ApiTypeError
 from petstore_api.exceptions import ApiValueError
 from petstore_api.exceptions import ApiKeyError
-from petstore_api.exceptions import ApiException
-
-# import models into sdk package
-from petstore_api.models.additional_properties_any_type import AdditionalPropertiesAnyType
-from petstore_api.models.additional_properties_array import AdditionalPropertiesArray
-from petstore_api.models.additional_properties_boolean import AdditionalPropertiesBoolean
-from petstore_api.models.additional_properties_class import AdditionalPropertiesClass
-from petstore_api.models.additional_properties_integer import AdditionalPropertiesInteger
-from petstore_api.models.additional_properties_number import AdditionalPropertiesNumber
-from petstore_api.models.additional_properties_object import AdditionalPropertiesObject
-from petstore_api.models.additional_properties_string import AdditionalPropertiesString
-from petstore_api.models.animal import Animal
-from petstore_api.models.api_response import ApiResponse
-from petstore_api.models.array_of_array_of_number_only import ArrayOfArrayOfNumberOnly
-from petstore_api.models.array_of_number_only import ArrayOfNumberOnly
-from petstore_api.models.array_test import ArrayTest
-from petstore_api.models.capitalization import Capitalization
-from petstore_api.models.cat import Cat
-from petstore_api.models.cat_all_of import CatAllOf
-from petstore_api.models.category import Category
-from petstore_api.models.child import Child
-from petstore_api.models.child_all_of import ChildAllOf
-from petstore_api.models.child_cat import ChildCat
-from petstore_api.models.child_cat_all_of import ChildCatAllOf
-from petstore_api.models.child_dog import ChildDog
-from petstore_api.models.child_dog_all_of import ChildDogAllOf
-from petstore_api.models.child_lizard import ChildLizard
-from petstore_api.models.child_lizard_all_of import ChildLizardAllOf
-from petstore_api.models.class_model import ClassModel
-from petstore_api.models.client import Client
-from petstore_api.models.dog import Dog
-from petstore_api.models.dog_all_of import DogAllOf
-from petstore_api.models.enum_arrays import EnumArrays
-from petstore_api.models.enum_class import EnumClass
-from petstore_api.models.enum_test import EnumTest
-from petstore_api.models.file import File
-from petstore_api.models.file_schema_test_class import FileSchemaTestClass
-from petstore_api.models.format_test import FormatTest
-from petstore_api.models.grandparent import Grandparent
-from petstore_api.models.grandparent_animal import GrandparentAnimal
-from petstore_api.models.has_only_read_only import HasOnlyReadOnly
-from petstore_api.models.list import List
-from petstore_api.models.map_test import MapTest
-from petstore_api.models.mixed_properties_and_additional_properties_class import MixedPropertiesAndAdditionalPropertiesClass
-from petstore_api.models.model200_response import Model200Response
-from petstore_api.models.model_return import ModelReturn
-from petstore_api.models.name import Name
-from petstore_api.models.number_only import NumberOnly
-from petstore_api.models.order import Order
-from petstore_api.models.outer_composite import OuterComposite
-from petstore_api.models.outer_enum import OuterEnum
-from petstore_api.models.outer_number import OuterNumber
-from petstore_api.models.parent import Parent
-from petstore_api.models.parent_all_of import ParentAllOf
-from petstore_api.models.parent_pet import ParentPet
-from petstore_api.models.pet import Pet
-from petstore_api.models.player import Player
-from petstore_api.models.read_only_first import ReadOnlyFirst
-from petstore_api.models.special_model_name import SpecialModelName
-from petstore_api.models.string_boolean_map import StringBooleanMap
-from petstore_api.models.tag import Tag
-from petstore_api.models.type_holder_default import TypeHolderDefault
-from petstore_api.models.type_holder_example import TypeHolderExample
-from petstore_api.models.user import User
-from petstore_api.models.xml_item import XmlItem
+from petstore_api.exceptions import ApiException
\ No newline at end of file
diff --git a/samples/client/petstore/python-experimental/petstore_api/api/another_fake_api.py b/samples/client/petstore/python-experimental/petstore_api/api/another_fake_api.py
index b7ea5e549329..3f277311b8fb 100644
--- a/samples/client/petstore/python-experimental/petstore_api/api/another_fake_api.py
+++ b/samples/client/petstore/python-experimental/petstore_api/api/another_fake_api.py
@@ -34,7 +34,7 @@
     str,
     validate_and_convert_types
 )
-from petstore_api.models import client
+from petstore_api.model import client
 
 
 class AnotherFakeApi(object):
diff --git a/samples/client/petstore/python-experimental/petstore_api/api/fake_api.py b/samples/client/petstore/python-experimental/petstore_api/api/fake_api.py
index e97902bb9a2b..a05c8e947b31 100644
--- a/samples/client/petstore/python-experimental/petstore_api/api/fake_api.py
+++ b/samples/client/petstore/python-experimental/petstore_api/api/fake_api.py
@@ -34,13 +34,13 @@
     str,
     validate_and_convert_types
 )
-from petstore_api.models import xml_item
-from petstore_api.models import outer_composite
-from petstore_api.models import outer_enum
-from petstore_api.models import outer_number
-from petstore_api.models import file_schema_test_class
-from petstore_api.models import user
-from petstore_api.models import client
+from petstore_api.model import xml_item
+from petstore_api.model import outer_composite
+from petstore_api.model import outer_enum
+from petstore_api.model import outer_number
+from petstore_api.model import file_schema_test_class
+from petstore_api.model import user
+from petstore_api.model import client
 
 
 class FakeApi(object):
diff --git a/samples/client/petstore/python-experimental/petstore_api/api/fake_classname_tags_123_api.py b/samples/client/petstore/python-experimental/petstore_api/api/fake_classname_tags_123_api.py
index 863e64beb0b5..be57432ae68d 100644
--- a/samples/client/petstore/python-experimental/petstore_api/api/fake_classname_tags_123_api.py
+++ b/samples/client/petstore/python-experimental/petstore_api/api/fake_classname_tags_123_api.py
@@ -34,7 +34,7 @@
     str,
     validate_and_convert_types
 )
-from petstore_api.models import client
+from petstore_api.model import client
 
 
 class FakeClassnameTags123Api(object):
diff --git a/samples/client/petstore/python-experimental/petstore_api/api/pet_api.py b/samples/client/petstore/python-experimental/petstore_api/api/pet_api.py
index 3d289a669882..6ec1e6d5c5cd 100644
--- a/samples/client/petstore/python-experimental/petstore_api/api/pet_api.py
+++ b/samples/client/petstore/python-experimental/petstore_api/api/pet_api.py
@@ -34,8 +34,8 @@
     str,
     validate_and_convert_types
 )
-from petstore_api.models import pet
-from petstore_api.models import api_response
+from petstore_api.model import pet
+from petstore_api.model import api_response
 
 
 class PetApi(object):
diff --git a/samples/client/petstore/python-experimental/petstore_api/api/store_api.py b/samples/client/petstore/python-experimental/petstore_api/api/store_api.py
index bcae5aab2a60..e612a43704f2 100644
--- a/samples/client/petstore/python-experimental/petstore_api/api/store_api.py
+++ b/samples/client/petstore/python-experimental/petstore_api/api/store_api.py
@@ -34,7 +34,7 @@
     str,
     validate_and_convert_types
 )
-from petstore_api.models import order
+from petstore_api.model import order
 
 
 class StoreApi(object):
diff --git a/samples/client/petstore/python-experimental/petstore_api/api/user_api.py b/samples/client/petstore/python-experimental/petstore_api/api/user_api.py
index 1362c5e31105..930ae821f2cb 100644
--- a/samples/client/petstore/python-experimental/petstore_api/api/user_api.py
+++ b/samples/client/petstore/python-experimental/petstore_api/api/user_api.py
@@ -34,7 +34,7 @@
     str,
     validate_and_convert_types
 )
-from petstore_api.models import user
+from petstore_api.model import user
 
 
 class UserApi(object):
diff --git a/samples/client/petstore/python-experimental/petstore_api/apis/__init__.py b/samples/client/petstore/python-experimental/petstore_api/apis/__init__.py
new file mode 100644
index 000000000000..f309caa3e651
--- /dev/null
+++ b/samples/client/petstore/python-experimental/petstore_api/apis/__init__.py
@@ -0,0 +1,20 @@
+# coding: utf-8
+
+# flake8: noqa
+
+# import all apis into this package
+# if you have many ampis here with many many models used in each api this may
+# raise a RecursionError
+# to avoid this, import only the api that you directly need like:
+# from .api.pet_api import PetApi
+# or import this package, but before doing it, use:
+# import sys
+# sys.setrecursionlimit(n)
+
+# import apis into api package
+from petstore_api.api.another_fake_api import AnotherFakeApi
+from petstore_api.api.fake_api import FakeApi
+from petstore_api.api.fake_classname_tags_123_api import FakeClassnameTags123Api
+from petstore_api.api.pet_api import PetApi
+from petstore_api.api.store_api import StoreApi
+from petstore_api.api.user_api import UserApi
diff --git a/samples/client/petstore/python-experimental/petstore_api/model/__init__.py b/samples/client/petstore/python-experimental/petstore_api/model/__init__.py
new file mode 100644
index 000000000000..cfe32b784926
--- /dev/null
+++ b/samples/client/petstore/python-experimental/petstore_api/model/__init__.py
@@ -0,0 +1,5 @@
+# we can not import model classes here because that would create a circular
+# reference which would not work in python2
+# do not import all models into this module because that uses a lot of memory and stack frames
+# if you need the ability to import all models from one package, import them with
+# from {{packageName}.models import ModelA, ModelB
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_any_type.py b/samples/client/petstore/python-experimental/petstore_api/model/additional_properties_any_type.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/additional_properties_any_type.py
rename to samples/client/petstore/python-experimental/petstore_api/model/additional_properties_any_type.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_array.py b/samples/client/petstore/python-experimental/petstore_api/model/additional_properties_array.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/additional_properties_array.py
rename to samples/client/petstore/python-experimental/petstore_api/model/additional_properties_array.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_boolean.py b/samples/client/petstore/python-experimental/petstore_api/model/additional_properties_boolean.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/additional_properties_boolean.py
rename to samples/client/petstore/python-experimental/petstore_api/model/additional_properties_boolean.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_class.py b/samples/client/petstore/python-experimental/petstore_api/model/additional_properties_class.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/additional_properties_class.py
rename to samples/client/petstore/python-experimental/petstore_api/model/additional_properties_class.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_integer.py b/samples/client/petstore/python-experimental/petstore_api/model/additional_properties_integer.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/additional_properties_integer.py
rename to samples/client/petstore/python-experimental/petstore_api/model/additional_properties_integer.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_number.py b/samples/client/petstore/python-experimental/petstore_api/model/additional_properties_number.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/additional_properties_number.py
rename to samples/client/petstore/python-experimental/petstore_api/model/additional_properties_number.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_object.py b/samples/client/petstore/python-experimental/petstore_api/model/additional_properties_object.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/additional_properties_object.py
rename to samples/client/petstore/python-experimental/petstore_api/model/additional_properties_object.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_string.py b/samples/client/petstore/python-experimental/petstore_api/model/additional_properties_string.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/additional_properties_string.py
rename to samples/client/petstore/python-experimental/petstore_api/model/additional_properties_string.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/animal.py b/samples/client/petstore/python-experimental/petstore_api/model/animal.py
similarity index 97%
rename from samples/client/petstore/python-experimental/petstore_api/models/animal.py
rename to samples/client/petstore/python-experimental/petstore_api/model/animal.py
index 641c9c16e279..7ba62dad1622 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/animal.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/animal.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import cat
+    from petstore_api.model import cat
 except ImportError:
     cat = sys.modules[
-        'petstore_api.models.cat']
+        'petstore_api.model.cat']
 try:
-    from petstore_api.models import dog
+    from petstore_api.model import dog
 except ImportError:
     dog = sys.modules[
-        'petstore_api.models.dog']
+        'petstore_api.model.dog']
 
 
 class Animal(ModelNormal):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/api_response.py b/samples/client/petstore/python-experimental/petstore_api/model/api_response.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/api_response.py
rename to samples/client/petstore/python-experimental/petstore_api/model/api_response.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/array_of_array_of_number_only.py b/samples/client/petstore/python-experimental/petstore_api/model/array_of_array_of_number_only.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/array_of_array_of_number_only.py
rename to samples/client/petstore/python-experimental/petstore_api/model/array_of_array_of_number_only.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/array_of_number_only.py b/samples/client/petstore/python-experimental/petstore_api/model/array_of_number_only.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/array_of_number_only.py
rename to samples/client/petstore/python-experimental/petstore_api/model/array_of_number_only.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/array_test.py b/samples/client/petstore/python-experimental/petstore_api/model/array_test.py
similarity index 98%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/array_test.py
rename to samples/client/petstore/python-experimental/petstore_api/model/array_test.py
index 0eed8d054611..e2bc76832b27 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/array_test.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/array_test.py
@@ -34,10 +34,10 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import read_only_first
+    from petstore_api.model import read_only_first
 except ImportError:
     read_only_first = sys.modules[
-        'petstore_api.models.read_only_first']
+        'petstore_api.model.read_only_first']
 
 
 class ArrayTest(ModelNormal):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/capitalization.py b/samples/client/petstore/python-experimental/petstore_api/model/capitalization.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/capitalization.py
rename to samples/client/petstore/python-experimental/petstore_api/model/capitalization.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/cat.py b/samples/client/petstore/python-experimental/petstore_api/model/cat.py
similarity index 98%
rename from samples/client/petstore/python-experimental/petstore_api/models/cat.py
rename to samples/client/petstore/python-experimental/petstore_api/model/cat.py
index 9620612169bf..b40a97dbab9a 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/cat.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/cat.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import animal
+    from petstore_api.model import animal
 except ImportError:
     animal = sys.modules[
-        'petstore_api.models.animal']
+        'petstore_api.model.animal']
 try:
-    from petstore_api.models import cat_all_of
+    from petstore_api.model import cat_all_of
 except ImportError:
     cat_all_of = sys.modules[
-        'petstore_api.models.cat_all_of']
+        'petstore_api.model.cat_all_of']
 
 
 class Cat(ModelComposed):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/cat_all_of.py b/samples/client/petstore/python-experimental/petstore_api/model/cat_all_of.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/cat_all_of.py
rename to samples/client/petstore/python-experimental/petstore_api/model/cat_all_of.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/category.py b/samples/client/petstore/python-experimental/petstore_api/model/category.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/category.py
rename to samples/client/petstore/python-experimental/petstore_api/model/category.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child.py b/samples/client/petstore/python-experimental/petstore_api/model/child.py
similarity index 98%
rename from samples/client/petstore/python-experimental/petstore_api/models/child.py
rename to samples/client/petstore/python-experimental/petstore_api/model/child.py
index 7be69a7d5280..37c138d6a488 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/child.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/child.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import child_all_of
+    from petstore_api.model import child_all_of
 except ImportError:
     child_all_of = sys.modules[
-        'petstore_api.models.child_all_of']
+        'petstore_api.model.child_all_of']
 try:
-    from petstore_api.models import parent
+    from petstore_api.model import parent
 except ImportError:
     parent = sys.modules[
-        'petstore_api.models.parent']
+        'petstore_api.model.parent']
 
 
 class Child(ModelComposed):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child_all_of.py b/samples/client/petstore/python-experimental/petstore_api/model/child_all_of.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/child_all_of.py
rename to samples/client/petstore/python-experimental/petstore_api/model/child_all_of.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child_cat.py b/samples/client/petstore/python-experimental/petstore_api/model/child_cat.py
similarity index 97%
rename from samples/client/petstore/python-experimental/petstore_api/models/child_cat.py
rename to samples/client/petstore/python-experimental/petstore_api/model/child_cat.py
index 873c3bc76cf7..6d42f11a18ff 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/child_cat.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/child_cat.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import child_cat_all_of
+    from petstore_api.model import child_cat_all_of
 except ImportError:
     child_cat_all_of = sys.modules[
-        'petstore_api.models.child_cat_all_of']
+        'petstore_api.model.child_cat_all_of']
 try:
-    from petstore_api.models import parent_pet
+    from petstore_api.model import parent_pet
 except ImportError:
     parent_pet = sys.modules[
-        'petstore_api.models.parent_pet']
+        'petstore_api.model.parent_pet']
 
 
 class ChildCat(ModelComposed):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child_cat_all_of.py b/samples/client/petstore/python-experimental/petstore_api/model/child_cat_all_of.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/child_cat_all_of.py
rename to samples/client/petstore/python-experimental/petstore_api/model/child_cat_all_of.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child_dog.py b/samples/client/petstore/python-experimental/petstore_api/model/child_dog.py
similarity index 97%
rename from samples/client/petstore/python-experimental/petstore_api/models/child_dog.py
rename to samples/client/petstore/python-experimental/petstore_api/model/child_dog.py
index a49f042cf74d..b7a93571a6a0 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/child_dog.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/child_dog.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import child_dog_all_of
+    from petstore_api.model import child_dog_all_of
 except ImportError:
     child_dog_all_of = sys.modules[
-        'petstore_api.models.child_dog_all_of']
+        'petstore_api.model.child_dog_all_of']
 try:
-    from petstore_api.models import parent_pet
+    from petstore_api.model import parent_pet
 except ImportError:
     parent_pet = sys.modules[
-        'petstore_api.models.parent_pet']
+        'petstore_api.model.parent_pet']
 
 
 class ChildDog(ModelComposed):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child_dog_all_of.py b/samples/client/petstore/python-experimental/petstore_api/model/child_dog_all_of.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/child_dog_all_of.py
rename to samples/client/petstore/python-experimental/petstore_api/model/child_dog_all_of.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child_lizard.py b/samples/client/petstore/python-experimental/petstore_api/model/child_lizard.py
similarity index 97%
rename from samples/client/petstore/python-experimental/petstore_api/models/child_lizard.py
rename to samples/client/petstore/python-experimental/petstore_api/model/child_lizard.py
index 0f11243a2493..978fea14a183 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/child_lizard.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/child_lizard.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import child_lizard_all_of
+    from petstore_api.model import child_lizard_all_of
 except ImportError:
     child_lizard_all_of = sys.modules[
-        'petstore_api.models.child_lizard_all_of']
+        'petstore_api.model.child_lizard_all_of']
 try:
-    from petstore_api.models import parent_pet
+    from petstore_api.model import parent_pet
 except ImportError:
     parent_pet = sys.modules[
-        'petstore_api.models.parent_pet']
+        'petstore_api.model.parent_pet']
 
 
 class ChildLizard(ModelComposed):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child_lizard_all_of.py b/samples/client/petstore/python-experimental/petstore_api/model/child_lizard_all_of.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/child_lizard_all_of.py
rename to samples/client/petstore/python-experimental/petstore_api/model/child_lizard_all_of.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/class_model.py b/samples/client/petstore/python-experimental/petstore_api/model/class_model.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/class_model.py
rename to samples/client/petstore/python-experimental/petstore_api/model/class_model.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/client.py b/samples/client/petstore/python-experimental/petstore_api/model/client.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/client.py
rename to samples/client/petstore/python-experimental/petstore_api/model/client.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/dog.py b/samples/client/petstore/python-experimental/petstore_api/model/dog.py
similarity index 98%
rename from samples/client/petstore/python-experimental/petstore_api/models/dog.py
rename to samples/client/petstore/python-experimental/petstore_api/model/dog.py
index f9b93eebc78f..547eba90c2b1 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/dog.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/dog.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import animal
+    from petstore_api.model import animal
 except ImportError:
     animal = sys.modules[
-        'petstore_api.models.animal']
+        'petstore_api.model.animal']
 try:
-    from petstore_api.models import dog_all_of
+    from petstore_api.model import dog_all_of
 except ImportError:
     dog_all_of = sys.modules[
-        'petstore_api.models.dog_all_of']
+        'petstore_api.model.dog_all_of']
 
 
 class Dog(ModelComposed):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/dog_all_of.py b/samples/client/petstore/python-experimental/petstore_api/model/dog_all_of.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/dog_all_of.py
rename to samples/client/petstore/python-experimental/petstore_api/model/dog_all_of.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/enum_arrays.py b/samples/client/petstore/python-experimental/petstore_api/model/enum_arrays.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/enum_arrays.py
rename to samples/client/petstore/python-experimental/petstore_api/model/enum_arrays.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/enum_class.py b/samples/client/petstore/python-experimental/petstore_api/model/enum_class.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/enum_class.py
rename to samples/client/petstore/python-experimental/petstore_api/model/enum_class.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/enum_test.py b/samples/client/petstore/python-experimental/petstore_api/model/enum_test.py
similarity index 98%
rename from samples/client/petstore/python-experimental/petstore_api/models/enum_test.py
rename to samples/client/petstore/python-experimental/petstore_api/model/enum_test.py
index 71cf60fd4823..bc0d1025261f 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/enum_test.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/enum_test.py
@@ -34,10 +34,10 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import outer_enum
+    from petstore_api.model import outer_enum
 except ImportError:
     outer_enum = sys.modules[
-        'petstore_api.models.outer_enum']
+        'petstore_api.model.outer_enum']
 
 
 class EnumTest(ModelNormal):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/file.py b/samples/client/petstore/python-experimental/petstore_api/model/file.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/file.py
rename to samples/client/petstore/python-experimental/petstore_api/model/file.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/file_schema_test_class.py b/samples/client/petstore/python-experimental/petstore_api/model/file_schema_test_class.py
similarity index 98%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/file_schema_test_class.py
rename to samples/client/petstore/python-experimental/petstore_api/model/file_schema_test_class.py
index 79e5638ccc94..0a9471e9e420 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/file_schema_test_class.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/file_schema_test_class.py
@@ -34,10 +34,10 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import file
+    from petstore_api.model import file
 except ImportError:
     file = sys.modules[
-        'petstore_api.models.file']
+        'petstore_api.model.file']
 
 
 class FileSchemaTestClass(ModelNormal):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/format_test.py b/samples/client/petstore/python-experimental/petstore_api/model/format_test.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/format_test.py
rename to samples/client/petstore/python-experimental/petstore_api/model/format_test.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/grandparent.py b/samples/client/petstore/python-experimental/petstore_api/model/grandparent.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/grandparent.py
rename to samples/client/petstore/python-experimental/petstore_api/model/grandparent.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/grandparent_animal.py b/samples/client/petstore/python-experimental/petstore_api/model/grandparent_animal.py
similarity index 95%
rename from samples/client/petstore/python-experimental/petstore_api/models/grandparent_animal.py
rename to samples/client/petstore/python-experimental/petstore_api/model/grandparent_animal.py
index 54dc5be641d7..81947e1c497d 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/grandparent_animal.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/grandparent_animal.py
@@ -34,25 +34,25 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import child_cat
+    from petstore_api.model import child_cat
 except ImportError:
     child_cat = sys.modules[
-        'petstore_api.models.child_cat']
+        'petstore_api.model.child_cat']
 try:
-    from petstore_api.models import child_dog
+    from petstore_api.model import child_dog
 except ImportError:
     child_dog = sys.modules[
-        'petstore_api.models.child_dog']
+        'petstore_api.model.child_dog']
 try:
-    from petstore_api.models import child_lizard
+    from petstore_api.model import child_lizard
 except ImportError:
     child_lizard = sys.modules[
-        'petstore_api.models.child_lizard']
+        'petstore_api.model.child_lizard']
 try:
-    from petstore_api.models import parent_pet
+    from petstore_api.model import parent_pet
 except ImportError:
     parent_pet = sys.modules[
-        'petstore_api.models.parent_pet']
+        'petstore_api.model.parent_pet']
 
 
 class GrandparentAnimal(ModelNormal):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/has_only_read_only.py b/samples/client/petstore/python-experimental/petstore_api/model/has_only_read_only.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/has_only_read_only.py
rename to samples/client/petstore/python-experimental/petstore_api/model/has_only_read_only.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/list.py b/samples/client/petstore/python-experimental/petstore_api/model/list.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/list.py
rename to samples/client/petstore/python-experimental/petstore_api/model/list.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/map_test.py b/samples/client/petstore/python-experimental/petstore_api/model/map_test.py
similarity index 98%
rename from samples/client/petstore/python-experimental/petstore_api/models/map_test.py
rename to samples/client/petstore/python-experimental/petstore_api/model/map_test.py
index 45be8a1fecfd..a22af06ce4fd 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/map_test.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/map_test.py
@@ -34,10 +34,10 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import string_boolean_map
+    from petstore_api.model import string_boolean_map
 except ImportError:
     string_boolean_map = sys.modules[
-        'petstore_api.models.string_boolean_map']
+        'petstore_api.model.string_boolean_map']
 
 
 class MapTest(ModelNormal):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/mixed_properties_and_additional_properties_class.py b/samples/client/petstore/python-experimental/petstore_api/model/mixed_properties_and_additional_properties_class.py
similarity index 98%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/mixed_properties_and_additional_properties_class.py
rename to samples/client/petstore/python-experimental/petstore_api/model/mixed_properties_and_additional_properties_class.py
index 0e584ebd43e9..a0fcac2eb019 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/mixed_properties_and_additional_properties_class.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/mixed_properties_and_additional_properties_class.py
@@ -34,10 +34,10 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import animal
+    from petstore_api.model import animal
 except ImportError:
     animal = sys.modules[
-        'petstore_api.models.animal']
+        'petstore_api.model.animal']
 
 
 class MixedPropertiesAndAdditionalPropertiesClass(ModelNormal):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/model200_response.py b/samples/client/petstore/python-experimental/petstore_api/model/model200_response.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/model200_response.py
rename to samples/client/petstore/python-experimental/petstore_api/model/model200_response.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/model_return.py b/samples/client/petstore/python-experimental/petstore_api/model/model_return.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/model_return.py
rename to samples/client/petstore/python-experimental/petstore_api/model/model_return.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/name.py b/samples/client/petstore/python-experimental/petstore_api/model/name.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/name.py
rename to samples/client/petstore/python-experimental/petstore_api/model/name.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/number_only.py b/samples/client/petstore/python-experimental/petstore_api/model/number_only.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/number_only.py
rename to samples/client/petstore/python-experimental/petstore_api/model/number_only.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/order.py b/samples/client/petstore/python-experimental/petstore_api/model/order.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/order.py
rename to samples/client/petstore/python-experimental/petstore_api/model/order.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/outer_composite.py b/samples/client/petstore/python-experimental/petstore_api/model/outer_composite.py
similarity index 98%
rename from samples/client/petstore/python-experimental/petstore_api/models/outer_composite.py
rename to samples/client/petstore/python-experimental/petstore_api/model/outer_composite.py
index a64cbe37592c..5614b9afe422 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/outer_composite.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/outer_composite.py
@@ -34,10 +34,10 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import outer_number
+    from petstore_api.model import outer_number
 except ImportError:
     outer_number = sys.modules[
-        'petstore_api.models.outer_number']
+        'petstore_api.model.outer_number']
 
 
 class OuterComposite(ModelNormal):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/outer_enum.py b/samples/client/petstore/python-experimental/petstore_api/model/outer_enum.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/outer_enum.py
rename to samples/client/petstore/python-experimental/petstore_api/model/outer_enum.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/outer_number.py b/samples/client/petstore/python-experimental/petstore_api/model/outer_number.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/outer_number.py
rename to samples/client/petstore/python-experimental/petstore_api/model/outer_number.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/parent.py b/samples/client/petstore/python-experimental/petstore_api/model/parent.py
similarity index 97%
rename from samples/client/petstore/python-experimental/petstore_api/models/parent.py
rename to samples/client/petstore/python-experimental/petstore_api/model/parent.py
index 5d33beb6979d..a855a3ffd014 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/parent.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/parent.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import grandparent
+    from petstore_api.model import grandparent
 except ImportError:
     grandparent = sys.modules[
-        'petstore_api.models.grandparent']
+        'petstore_api.model.grandparent']
 try:
-    from petstore_api.models import parent_all_of
+    from petstore_api.model import parent_all_of
 except ImportError:
     parent_all_of = sys.modules[
-        'petstore_api.models.parent_all_of']
+        'petstore_api.model.parent_all_of']
 
 
 class Parent(ModelComposed):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/parent_all_of.py b/samples/client/petstore/python-experimental/petstore_api/model/parent_all_of.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/parent_all_of.py
rename to samples/client/petstore/python-experimental/petstore_api/model/parent_all_of.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/parent_pet.py b/samples/client/petstore/python-experimental/petstore_api/model/parent_pet.py
similarity index 96%
rename from samples/client/petstore/python-experimental/petstore_api/models/parent_pet.py
rename to samples/client/petstore/python-experimental/petstore_api/model/parent_pet.py
index 4635ac947806..0b0b30c656f5 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/parent_pet.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/parent_pet.py
@@ -34,25 +34,25 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import child_cat
+    from petstore_api.model import child_cat
 except ImportError:
     child_cat = sys.modules[
-        'petstore_api.models.child_cat']
+        'petstore_api.model.child_cat']
 try:
-    from petstore_api.models import child_dog
+    from petstore_api.model import child_dog
 except ImportError:
     child_dog = sys.modules[
-        'petstore_api.models.child_dog']
+        'petstore_api.model.child_dog']
 try:
-    from petstore_api.models import child_lizard
+    from petstore_api.model import child_lizard
 except ImportError:
     child_lizard = sys.modules[
-        'petstore_api.models.child_lizard']
+        'petstore_api.model.child_lizard']
 try:
-    from petstore_api.models import grandparent_animal
+    from petstore_api.model import grandparent_animal
 except ImportError:
     grandparent_animal = sys.modules[
-        'petstore_api.models.grandparent_animal']
+        'petstore_api.model.grandparent_animal']
 
 
 class ParentPet(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/pet.py b/samples/client/petstore/python-experimental/petstore_api/model/pet.py
similarity index 97%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/pet.py
rename to samples/client/petstore/python-experimental/petstore_api/model/pet.py
index c93acd53c96c..742d7cdf04a8 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/pet.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/pet.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import category
+    from petstore_api.model import category
 except ImportError:
     category = sys.modules[
-        'petstore_api.models.category']
+        'petstore_api.model.category']
 try:
-    from petstore_api.models import tag
+    from petstore_api.model import tag
 except ImportError:
     tag = sys.modules[
-        'petstore_api.models.tag']
+        'petstore_api.model.tag']
 
 
 class Pet(ModelNormal):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/player.py b/samples/client/petstore/python-experimental/petstore_api/model/player.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/player.py
rename to samples/client/petstore/python-experimental/petstore_api/model/player.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/read_only_first.py b/samples/client/petstore/python-experimental/petstore_api/model/read_only_first.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/read_only_first.py
rename to samples/client/petstore/python-experimental/petstore_api/model/read_only_first.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/special_model_name.py b/samples/client/petstore/python-experimental/petstore_api/model/special_model_name.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/special_model_name.py
rename to samples/client/petstore/python-experimental/petstore_api/model/special_model_name.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/string_boolean_map.py b/samples/client/petstore/python-experimental/petstore_api/model/string_boolean_map.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/string_boolean_map.py
rename to samples/client/petstore/python-experimental/petstore_api/model/string_boolean_map.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/tag.py b/samples/client/petstore/python-experimental/petstore_api/model/tag.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/tag.py
rename to samples/client/petstore/python-experimental/petstore_api/model/tag.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/type_holder_default.py b/samples/client/petstore/python-experimental/petstore_api/model/type_holder_default.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/type_holder_default.py
rename to samples/client/petstore/python-experimental/petstore_api/model/type_holder_default.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/type_holder_example.py b/samples/client/petstore/python-experimental/petstore_api/model/type_holder_example.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/type_holder_example.py
rename to samples/client/petstore/python-experimental/petstore_api/model/type_holder_example.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/user.py b/samples/client/petstore/python-experimental/petstore_api/model/user.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/user.py
rename to samples/client/petstore/python-experimental/petstore_api/model/user.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/xml_item.py b/samples/client/petstore/python-experimental/petstore_api/model/xml_item.py
similarity index 100%
rename from samples/client/petstore/python-experimental/petstore_api/models/xml_item.py
rename to samples/client/petstore/python-experimental/petstore_api/model/xml_item.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/__init__.py b/samples/client/petstore/python-experimental/petstore_api/models/__init__.py
index e02c66519259..51bdb1a85a57 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/__init__.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/__init__.py
@@ -1,15 +1,75 @@
 # coding: utf-8
 
 # flake8: noqa
-"""
-    OpenAPI Petstore
 
-    This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
+# import all models into this package
+# if you have many models here with many references from one model to another this may
+# raise a RecursionError
+# to avoid this, import only the models that you directly need like:
+# from from petstore_api.model.pet import Pet
+# or import this package, but before doing it, use:
+# import sys
+# sys.setrecursionlimit(n)
 
-    The version of the OpenAPI document: 1.0.0
-    Generated by: https://openapi-generator.tech
-"""
-
-
-# we can not import model classes here because that would create a circular
-# reference which would not work in python2
+from petstore_api.model.additional_properties_any_type import AdditionalPropertiesAnyType
+from petstore_api.model.additional_properties_array import AdditionalPropertiesArray
+from petstore_api.model.additional_properties_boolean import AdditionalPropertiesBoolean
+from petstore_api.model.additional_properties_class import AdditionalPropertiesClass
+from petstore_api.model.additional_properties_integer import AdditionalPropertiesInteger
+from petstore_api.model.additional_properties_number import AdditionalPropertiesNumber
+from petstore_api.model.additional_properties_object import AdditionalPropertiesObject
+from petstore_api.model.additional_properties_string import AdditionalPropertiesString
+from petstore_api.model.animal import Animal
+from petstore_api.model.api_response import ApiResponse
+from petstore_api.model.array_of_array_of_number_only import ArrayOfArrayOfNumberOnly
+from petstore_api.model.array_of_number_only import ArrayOfNumberOnly
+from petstore_api.model.array_test import ArrayTest
+from petstore_api.model.capitalization import Capitalization
+from petstore_api.model.cat import Cat
+from petstore_api.model.cat_all_of import CatAllOf
+from petstore_api.model.category import Category
+from petstore_api.model.child import Child
+from petstore_api.model.child_all_of import ChildAllOf
+from petstore_api.model.child_cat import ChildCat
+from petstore_api.model.child_cat_all_of import ChildCatAllOf
+from petstore_api.model.child_dog import ChildDog
+from petstore_api.model.child_dog_all_of import ChildDogAllOf
+from petstore_api.model.child_lizard import ChildLizard
+from petstore_api.model.child_lizard_all_of import ChildLizardAllOf
+from petstore_api.model.class_model import ClassModel
+from petstore_api.model.client import Client
+from petstore_api.model.dog import Dog
+from petstore_api.model.dog_all_of import DogAllOf
+from petstore_api.model.enum_arrays import EnumArrays
+from petstore_api.model.enum_class import EnumClass
+from petstore_api.model.enum_test import EnumTest
+from petstore_api.model.file import File
+from petstore_api.model.file_schema_test_class import FileSchemaTestClass
+from petstore_api.model.format_test import FormatTest
+from petstore_api.model.grandparent import Grandparent
+from petstore_api.model.grandparent_animal import GrandparentAnimal
+from petstore_api.model.has_only_read_only import HasOnlyReadOnly
+from petstore_api.model.list import List
+from petstore_api.model.map_test import MapTest
+from petstore_api.model.mixed_properties_and_additional_properties_class import MixedPropertiesAndAdditionalPropertiesClass
+from petstore_api.model.model200_response import Model200Response
+from petstore_api.model.model_return import ModelReturn
+from petstore_api.model.name import Name
+from petstore_api.model.number_only import NumberOnly
+from petstore_api.model.order import Order
+from petstore_api.model.outer_composite import OuterComposite
+from petstore_api.model.outer_enum import OuterEnum
+from petstore_api.model.outer_number import OuterNumber
+from petstore_api.model.parent import Parent
+from petstore_api.model.parent_all_of import ParentAllOf
+from petstore_api.model.parent_pet import ParentPet
+from petstore_api.model.pet import Pet
+from petstore_api.model.player import Player
+from petstore_api.model.read_only_first import ReadOnlyFirst
+from petstore_api.model.special_model_name import SpecialModelName
+from petstore_api.model.string_boolean_map import StringBooleanMap
+from petstore_api.model.tag import Tag
+from petstore_api.model.type_holder_default import TypeHolderDefault
+from petstore_api.model.type_holder_example import TypeHolderExample
+from petstore_api.model.user import User
+from petstore_api.model.xml_item import XmlItem
diff --git a/samples/client/petstore/python-experimental/test/test_additional_properties_any_type.py b/samples/client/petstore/python-experimental/test/test_additional_properties_any_type.py
index 4b6739a1faf3..ce985f76ed9e 100644
--- a/samples/client/petstore/python-experimental/test/test_additional_properties_any_type.py
+++ b/samples/client/petstore/python-experimental/test/test_additional_properties_any_type.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.additional_properties_any_type import AdditionalPropertiesAnyType  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.additional_properties_any_type import AdditionalPropertiesAnyType
 
 
 class TestAdditionalPropertiesAnyType(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testAdditionalPropertiesAnyType(self):
         """Test AdditionalPropertiesAnyType"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.additional_properties_any_type.AdditionalPropertiesAnyType()  # noqa: E501
+        # model = AdditionalPropertiesAnyType()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_additional_properties_array.py b/samples/client/petstore/python-experimental/test/test_additional_properties_array.py
index 6c86292cd4a4..f63ca82f6c22 100644
--- a/samples/client/petstore/python-experimental/test/test_additional_properties_array.py
+++ b/samples/client/petstore/python-experimental/test/test_additional_properties_array.py
@@ -5,21 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.additional_properties_array import AdditionalPropertiesArray  # noqa: E501
-from petstore_api.rest import ApiException
-from petstore_api.exceptions import ApiTypeError
-
-import datetime
+from petstore_api.model.additional_properties_array import AdditionalPropertiesArray
 
 
 class TestAdditionalPropertiesArray(unittest.TestCase):
@@ -37,6 +33,7 @@ def testAdditionalPropertiesArray(self):
         model = AdditionalPropertiesArray()
 
         # can make one with additional properties
+        import datetime
         some_val = []
         model = AdditionalPropertiesArray(some_key=some_val)
         assert model['some_key'] == some_val
@@ -45,7 +42,7 @@ def testAdditionalPropertiesArray(self):
         assert model['some_key'] == some_val
 
         # type checking works on additional properties
-        with self.assertRaises(ApiTypeError) as exc:
+        with self.assertRaises(petstore_api.ApiTypeError) as exc:
             model = AdditionalPropertiesArray(some_key='some string')
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_additional_properties_boolean.py b/samples/client/petstore/python-experimental/test/test_additional_properties_boolean.py
index 33bcfb90bb61..e5a13891c098 100644
--- a/samples/client/petstore/python-experimental/test/test_additional_properties_boolean.py
+++ b/samples/client/petstore/python-experimental/test/test_additional_properties_boolean.py
@@ -5,19 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.additional_properties_boolean import AdditionalPropertiesBoolean  # noqa: E501
-from petstore_api.rest import ApiException
-from petstore_api.exceptions import ApiTypeError
+from petstore_api.model.additional_properties_boolean import AdditionalPropertiesBoolean
 
 
 class TestAdditionalPropertiesBoolean(unittest.TestCase):
@@ -39,7 +37,7 @@ def testAdditionalPropertiesBoolean(self):
         assert model['some_key'] == True
 
         # type checking works on additional properties
-        with self.assertRaises(ApiTypeError) as exc:
+        with self.assertRaises(petstore_api.ApiTypeError) as exc:
             model = AdditionalPropertiesBoolean(some_key='True')
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_additional_properties_class.py b/samples/client/petstore/python-experimental/test/test_additional_properties_class.py
index fc9df3bbb505..befc14455da2 100644
--- a/samples/client/petstore/python-experimental/test/test_additional_properties_class.py
+++ b/samples/client/petstore/python-experimental/test/test_additional_properties_class.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.additional_properties_class import AdditionalPropertiesClass  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.additional_properties_class import AdditionalPropertiesClass
 
 
 class TestAdditionalPropertiesClass(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testAdditionalPropertiesClass(self):
         """Test AdditionalPropertiesClass"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.additional_properties_class.AdditionalPropertiesClass()  # noqa: E501
+        # model = AdditionalPropertiesClass()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_additional_properties_integer.py b/samples/client/petstore/python-experimental/test/test_additional_properties_integer.py
index 0029cb9c84c5..0e08b8f87706 100644
--- a/samples/client/petstore/python-experimental/test/test_additional_properties_integer.py
+++ b/samples/client/petstore/python-experimental/test/test_additional_properties_integer.py
@@ -5,19 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.additional_properties_integer import AdditionalPropertiesInteger  # noqa: E501
-from petstore_api.rest import ApiException
-from petstore_api.exceptions import ApiTypeError
+from petstore_api.model.additional_properties_integer import AdditionalPropertiesInteger
 
 
 class TestAdditionalPropertiesInteger(unittest.TestCase):
@@ -39,7 +37,7 @@ def testAdditionalPropertiesInteger(self):
         assert model['some_key'] == 3
 
         # type checking works on additional properties
-        with self.assertRaises(ApiTypeError) as exc:
+        with self.assertRaises(petstore_api.ApiTypeError) as exc:
             model = AdditionalPropertiesInteger(some_key=11.3)
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_additional_properties_number.py b/samples/client/petstore/python-experimental/test/test_additional_properties_number.py
index 28d0b23377a6..90f4429e989f 100644
--- a/samples/client/petstore/python-experimental/test/test_additional_properties_number.py
+++ b/samples/client/petstore/python-experimental/test/test_additional_properties_number.py
@@ -5,19 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.additional_properties_number import AdditionalPropertiesNumber  # noqa: E501
-from petstore_api.rest import ApiException
-from petstore_api.exceptions import ApiTypeError
+from petstore_api.model.additional_properties_number import AdditionalPropertiesNumber
 
 
 class TestAdditionalPropertiesNumber(unittest.TestCase):
@@ -39,8 +37,9 @@ def testAdditionalPropertiesNumber(self):
         assert model['some_key'] == 11.3
 
         # type checking works on additional properties
-        with self.assertRaises(ApiTypeError) as exc:
+        with self.assertRaises(petstore_api.ApiTypeError) as exc:
             model = AdditionalPropertiesNumber(some_key=10)
 
+
 if __name__ == '__main__':
     unittest.main()
diff --git a/samples/client/petstore/python-experimental/test/test_additional_properties_object.py b/samples/client/petstore/python-experimental/test/test_additional_properties_object.py
index 3d135116736c..ded4a8e8a124 100644
--- a/samples/client/petstore/python-experimental/test/test_additional_properties_object.py
+++ b/samples/client/petstore/python-experimental/test/test_additional_properties_object.py
@@ -5,21 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.additional_properties_object import AdditionalPropertiesObject  # noqa: E501
-from petstore_api.rest import ApiException
-from petstore_api.exceptions import ApiTypeError
-
-import datetime
+from petstore_api.model.additional_properties_object import AdditionalPropertiesObject
 
 
 class TestAdditionalPropertiesObject(unittest.TestCase):
@@ -40,12 +36,13 @@ def testAdditionalPropertiesObject(self):
         some_val = {}
         model = AdditionalPropertiesObject(some_key=some_val)
         assert model['some_key'] == some_val
+        import datetime
         some_val = {'a': True, 'b': datetime.date(1970,1,1), 'c': datetime.datetime(1970,1,1), 'd': {}, 'e': 3.1, 'f': 1, 'g': [], 'h': 'hello'}
         model = AdditionalPropertiesObject(some_key=some_val)
         assert model['some_key'] == some_val
 
         # type checking works on additional properties
-        with self.assertRaises(ApiTypeError) as exc:
+        with self.assertRaises(petstore_api.ApiTypeError) as exc:
             model = AdditionalPropertiesObject(some_key='some string')
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_additional_properties_string.py b/samples/client/petstore/python-experimental/test/test_additional_properties_string.py
index 0276334ead53..cff2c31921fe 100644
--- a/samples/client/petstore/python-experimental/test/test_additional_properties_string.py
+++ b/samples/client/petstore/python-experimental/test/test_additional_properties_string.py
@@ -5,19 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.additional_properties_string import AdditionalPropertiesString  # noqa: E501
-from petstore_api.rest import ApiException
-from petstore_api.exceptions import ApiTypeError
+from petstore_api.model.additional_properties_string import AdditionalPropertiesString
 
 
 class TestAdditionalPropertiesString(unittest.TestCase):
@@ -39,7 +37,7 @@ def testAdditionalPropertiesString(self):
         assert model['some_key'] == 'some_val'
 
         # type checking works on additional properties
-        with self.assertRaises(ApiTypeError) as exc:
+        with self.assertRaises(petstore_api.ApiTypeError) as exc:
             model = AdditionalPropertiesString(some_key=True)
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_animal.py b/samples/client/petstore/python-experimental/test/test_animal.py
index 179f1fbd0e52..958f303f13e3 100644
--- a/samples/client/petstore/python-experimental/test/test_animal.py
+++ b/samples/client/petstore/python-experimental/test/test_animal.py
@@ -5,18 +5,27 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.animal import Animal  # noqa: E501
-from petstore_api.rest import ApiException
+try:
+    from petstore_api.model import cat
+except ImportError:
+    cat = sys.modules[
+        'petstore_api.model.cat']
+try:
+    from petstore_api.model import dog
+except ImportError:
+    dog = sys.modules[
+        'petstore_api.model.dog']
+from petstore_api.model.animal import Animal
 
 
 class TestAnimal(unittest.TestCase):
@@ -31,7 +40,7 @@ def tearDown(self):
     def testAnimal(self):
         """Test Animal"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.animal.Animal()  # noqa: E501
+        # model = Animal()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_another_fake_api.py b/samples/client/petstore/python-experimental/test/test_another_fake_api.py
index 4b80dc4eda52..f79966a26961 100644
--- a/samples/client/petstore/python-experimental/test/test_another_fake_api.py
+++ b/samples/client/petstore/python-experimental/test/test_another_fake_api.py
@@ -5,7 +5,7 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
@@ -16,20 +16,19 @@
 
 import petstore_api
 from petstore_api.api.another_fake_api import AnotherFakeApi  # noqa: E501
-from petstore_api.rest import ApiException
 
 
 class TestAnotherFakeApi(unittest.TestCase):
     """AnotherFakeApi unit test stubs"""
 
     def setUp(self):
-        self.api = petstore_api.api.another_fake_api.AnotherFakeApi()  # noqa: E501
+        self.api = AnotherFakeApi()  # noqa: E501
 
     def tearDown(self):
         pass
 
-    def test_test_special_tags(self):
-        """Test case for test_special_tags
+    def test_call_123_test_special_tags(self):
+        """Test case for call_123_test_special_tags
 
         To test special tags  # noqa: E501
         """
diff --git a/samples/client/petstore/python-experimental/test/test_api_response.py b/samples/client/petstore/python-experimental/test/test_api_response.py
index 5031b458a0db..9db92633f626 100644
--- a/samples/client/petstore/python-experimental/test/test_api_response.py
+++ b/samples/client/petstore/python-experimental/test/test_api_response.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.api_response import ApiResponse  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.api_response import ApiResponse
 
 
 class TestApiResponse(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testApiResponse(self):
         """Test ApiResponse"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.api_response.ApiResponse()  # noqa: E501
+        # model = ApiResponse()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_array_of_array_of_number_only.py b/samples/client/petstore/python-experimental/test/test_array_of_array_of_number_only.py
index a02233045421..4980ad17afb5 100644
--- a/samples/client/petstore/python-experimental/test/test_array_of_array_of_number_only.py
+++ b/samples/client/petstore/python-experimental/test/test_array_of_array_of_number_only.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.array_of_array_of_number_only import ArrayOfArrayOfNumberOnly  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.array_of_array_of_number_only import ArrayOfArrayOfNumberOnly
 
 
 class TestArrayOfArrayOfNumberOnly(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testArrayOfArrayOfNumberOnly(self):
         """Test ArrayOfArrayOfNumberOnly"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.array_of_array_of_number_only.ArrayOfArrayOfNumberOnly()  # noqa: E501
+        # model = ArrayOfArrayOfNumberOnly()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_array_of_number_only.py b/samples/client/petstore/python-experimental/test/test_array_of_number_only.py
index 1a928bf7d2e0..479c537cada7 100644
--- a/samples/client/petstore/python-experimental/test/test_array_of_number_only.py
+++ b/samples/client/petstore/python-experimental/test/test_array_of_number_only.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.array_of_number_only import ArrayOfNumberOnly  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.array_of_number_only import ArrayOfNumberOnly
 
 
 class TestArrayOfNumberOnly(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testArrayOfNumberOnly(self):
         """Test ArrayOfNumberOnly"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.array_of_number_only.ArrayOfNumberOnly()  # noqa: E501
+        # model = ArrayOfNumberOnly()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_array_test.py b/samples/client/petstore/python-experimental/test/test_array_test.py
index c56b77b77ee3..2426b27b7e46 100644
--- a/samples/client/petstore/python-experimental/test/test_array_test.py
+++ b/samples/client/petstore/python-experimental/test/test_array_test.py
@@ -5,18 +5,22 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.array_test import ArrayTest  # noqa: E501
-from petstore_api.rest import ApiException
+try:
+    from petstore_api.model import read_only_first
+except ImportError:
+    read_only_first = sys.modules[
+        'petstore_api.model.read_only_first']
+from petstore_api.model.array_test import ArrayTest
 
 
 class TestArrayTest(unittest.TestCase):
@@ -31,7 +35,7 @@ def tearDown(self):
     def testArrayTest(self):
         """Test ArrayTest"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.array_test.ArrayTest()  # noqa: E501
+        # model = ArrayTest()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_capitalization.py b/samples/client/petstore/python-experimental/test/test_capitalization.py
index 2ae7725b3f09..20d2649c01eb 100644
--- a/samples/client/petstore/python-experimental/test/test_capitalization.py
+++ b/samples/client/petstore/python-experimental/test/test_capitalization.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.capitalization import Capitalization  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.capitalization import Capitalization
 
 
 class TestCapitalization(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testCapitalization(self):
         """Test Capitalization"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.capitalization.Capitalization()  # noqa: E501
+        # model = Capitalization()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_cat.py b/samples/client/petstore/python-experimental/test/test_cat.py
index 5ebd7908d2db..64b525aaf118 100644
--- a/samples/client/petstore/python-experimental/test/test_cat.py
+++ b/samples/client/petstore/python-experimental/test/test_cat.py
@@ -5,18 +5,27 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.cat import Cat  # noqa: E501
-from petstore_api.rest import ApiException
+try:
+    from petstore_api.model import animal
+except ImportError:
+    animal = sys.modules[
+        'petstore_api.model.animal']
+try:
+    from petstore_api.model import cat_all_of
+except ImportError:
+    cat_all_of = sys.modules[
+        'petstore_api.model.cat_all_of']
+from petstore_api.model.cat import Cat
 
 
 class TestCat(unittest.TestCase):
@@ -31,7 +40,7 @@ def tearDown(self):
     def testCat(self):
         """Test Cat"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.cat.Cat()  # noqa: E501
+        # model = Cat()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_cat_all_of.py b/samples/client/petstore/python-experimental/test/test_cat_all_of.py
index 531443380c6e..a5bb91ac864e 100644
--- a/samples/client/petstore/python-experimental/test/test_cat_all_of.py
+++ b/samples/client/petstore/python-experimental/test/test_cat_all_of.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.cat_all_of import CatAllOf  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.cat_all_of import CatAllOf
 
 
 class TestCatAllOf(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testCatAllOf(self):
         """Test CatAllOf"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.cat_all_of.CatAllOf()  # noqa: E501
+        # model = CatAllOf()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_category.py b/samples/client/petstore/python-experimental/test/test_category.py
index 6a592521281e..59b64e5924a8 100644
--- a/samples/client/petstore/python-experimental/test/test_category.py
+++ b/samples/client/petstore/python-experimental/test/test_category.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.category import Category  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.category import Category
 
 
 class TestCategory(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testCategory(self):
         """Test Category"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.category.Category()  # noqa: E501
+        # model = Category()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_child.py b/samples/client/petstore/python-experimental/test/test_child.py
index 660cfe637d96..51c0bb129d24 100644
--- a/samples/client/petstore/python-experimental/test/test_child.py
+++ b/samples/client/petstore/python-experimental/test/test_child.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import child_all_of
+except ImportError:
+    child_all_of = sys.modules[
+        'petstore_api.model.child_all_of']
+try:
+    from petstore_api.model import parent
+except ImportError:
+    parent = sys.modules[
+        'petstore_api.model.parent']
+from petstore_api.model.child import Child
 
 
 class TestChild(unittest.TestCase):
@@ -33,7 +44,7 @@ def testChild(self):
         radio_waves = True
         tele_vision = True
         inter_net = True
-        child = petstore_api.Child(
+        child = Child(
             radio_waves=radio_waves,
             tele_vision=tele_vision,
             inter_net=inter_net
@@ -64,10 +75,10 @@ def testChild(self):
 
         # setting a value that doesn't exist raises an exception
         # with a key
-        with self.assertRaises(AttributeError):
+        with self.assertRaises(petstore_api.ApiAttributeError):
             child['invalid_variable'] = 'some value'
         # with setattr
-        with self.assertRaises(AttributeError):
+        with self.assertRaises(petstore_api.ApiAttributeError):
             setattr(child, 'invalid_variable', 'some value')
 
         # with hasattr
@@ -75,12 +86,12 @@ def testChild(self):
 
         # getting a value that doesn't exist raises an exception
         # with a key
-        with self.assertRaises(AttributeError):
+        with self.assertRaises(petstore_api.ApiAttributeError):
             invalid_variable = child['invalid_variable']
         # with getattr
         self.assertEquals(getattr(child, 'invalid_variable', 'some value'), 'some value')
 
-        with self.assertRaises(AttributeError):
+        with self.assertRaises(petstore_api.ApiAttributeError):
             invalid_variable = getattr(child, 'invalid_variable')
 
         # make sure that the ModelComposed class properties are correct
@@ -90,8 +101,8 @@ def testChild(self):
             {
                 'anyOf': [],
                 'allOf': [
-                    petstore_api.ChildAllOf,
-                    petstore_api.Parent,
+                    child_all_of.ChildAllOf,
+                    parent.Parent,
                 ],
                 'oneOf': [],
             }
@@ -99,9 +110,9 @@ def testChild(self):
         # model._composed_instances is a list of the instances that were
         # made from the anyOf/allOf/OneOf classes in model._composed_schemas()
         for composed_instance in child._composed_instances:
-            if composed_instance.__class__ == petstore_api.Parent:
+            if composed_instance.__class__ == parent.Parent:
                 parent_instance = composed_instance
-            elif composed_instance.__class__ == petstore_api.ChildAllOf:
+            elif composed_instance.__class__ == child_all_of.ChildAllOf:
                 child_allof_instance = composed_instance
         self.assertEqual(
             child._composed_instances,
@@ -132,12 +143,11 @@ def testChild(self):
 
         # including extra parameters raises an exception
         with self.assertRaises(petstore_api.ApiValueError):
-            child = petstore_api.Child(
+            child = Child(
                 radio_waves=radio_waves,
                 tele_vision=tele_vision,
                 inter_net=inter_net,
-                unknown_property='some value'
-            )
+                unknown_property='some value')
 
 if __name__ == '__main__':
     unittest.main()
diff --git a/samples/client/petstore/python-experimental/test/test_child_all_of.py b/samples/client/petstore/python-experimental/test/test_child_all_of.py
index e3f14035f625..96e479cf0796 100644
--- a/samples/client/petstore/python-experimental/test/test_child_all_of.py
+++ b/samples/client/petstore/python-experimental/test/test_child_all_of.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.child_all_of import ChildAllOf
 
 
 class TestChildAllOf(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testChildAllOf(self):
         """Test ChildAllOf"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ChildAllOf()  # noqa: E501
+        # model = ChildAllOf()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_child_cat.py b/samples/client/petstore/python-experimental/test/test_child_cat.py
index c42c3b583aae..34c085515a80 100644
--- a/samples/client/petstore/python-experimental/test/test_child_cat.py
+++ b/samples/client/petstore/python-experimental/test/test_child_cat.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import child_cat_all_of
+except ImportError:
+    child_cat_all_of = sys.modules[
+        'petstore_api.model.child_cat_all_of']
+try:
+    from petstore_api.model import parent_pet
+except ImportError:
+    parent_pet = sys.modules[
+        'petstore_api.model.parent_pet']
+from petstore_api.model.child_cat import ChildCat
 
 
 class TestChildCat(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testChildCat(self):
         """Test ChildCat"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ChildCat()  # noqa: E501
+        # model = ChildCat()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_child_cat_all_of.py b/samples/client/petstore/python-experimental/test/test_child_cat_all_of.py
index 3304a81a2321..2a7aab100fbf 100644
--- a/samples/client/petstore/python-experimental/test/test_child_cat_all_of.py
+++ b/samples/client/petstore/python-experimental/test/test_child_cat_all_of.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.child_cat_all_of import ChildCatAllOf
 
 
 class TestChildCatAllOf(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testChildCatAllOf(self):
         """Test ChildCatAllOf"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ChildCatAllOf()  # noqa: E501
+        # model = ChildCatAllOf()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_child_dog.py b/samples/client/petstore/python-experimental/test/test_child_dog.py
index 9c56f27bbc49..dfb09213e40c 100644
--- a/samples/client/petstore/python-experimental/test/test_child_dog.py
+++ b/samples/client/petstore/python-experimental/test/test_child_dog.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import child_dog_all_of
+except ImportError:
+    child_dog_all_of = sys.modules[
+        'petstore_api.model.child_dog_all_of']
+try:
+    from petstore_api.model import parent_pet
+except ImportError:
+    parent_pet = sys.modules[
+        'petstore_api.model.parent_pet']
+from petstore_api.model.child_dog import ChildDog
 
 
 class TestChildDog(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testChildDog(self):
         """Test ChildDog"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ChildDog()  # noqa: E501
+        # model = ChildDog()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_child_dog_all_of.py b/samples/client/petstore/python-experimental/test/test_child_dog_all_of.py
index a9124db412b7..ca75000c650e 100644
--- a/samples/client/petstore/python-experimental/test/test_child_dog_all_of.py
+++ b/samples/client/petstore/python-experimental/test/test_child_dog_all_of.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.child_dog_all_of import ChildDogAllOf
 
 
 class TestChildDogAllOf(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testChildDogAllOf(self):
         """Test ChildDogAllOf"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ChildDogAllOf()  # noqa: E501
+        # model = ChildDogAllOf()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_child_lizard.py b/samples/client/petstore/python-experimental/test/test_child_lizard.py
index 21ba88480aad..975dc1612a9f 100644
--- a/samples/client/petstore/python-experimental/test/test_child_lizard.py
+++ b/samples/client/petstore/python-experimental/test/test_child_lizard.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import child_lizard_all_of
+except ImportError:
+    child_lizard_all_of = sys.modules[
+        'petstore_api.model.child_lizard_all_of']
+try:
+    from petstore_api.model import parent_pet
+except ImportError:
+    parent_pet = sys.modules[
+        'petstore_api.model.parent_pet']
+from petstore_api.model.child_lizard import ChildLizard
 
 
 class TestChildLizard(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testChildLizard(self):
         """Test ChildLizard"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ChildLizard()  # noqa: E501
+        # model = ChildLizard()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_child_lizard_all_of.py b/samples/client/petstore/python-experimental/test/test_child_lizard_all_of.py
index 824e376f855b..1b3bf4dba943 100644
--- a/samples/client/petstore/python-experimental/test/test_child_lizard_all_of.py
+++ b/samples/client/petstore/python-experimental/test/test_child_lizard_all_of.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.child_lizard_all_of import ChildLizardAllOf
 
 
 class TestChildLizardAllOf(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testChildLizardAllOf(self):
         """Test ChildLizardAllOf"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ChildLizardAllOf()  # noqa: E501
+        # model = ChildLizardAllOf()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_class_model.py b/samples/client/petstore/python-experimental/test/test_class_model.py
index 12b7fb99402e..060df39e4b5e 100644
--- a/samples/client/petstore/python-experimental/test/test_class_model.py
+++ b/samples/client/petstore/python-experimental/test/test_class_model.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.class_model import ClassModel  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.class_model import ClassModel
 
 
 class TestClassModel(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testClassModel(self):
         """Test ClassModel"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.class_model.ClassModel()  # noqa: E501
+        # model = ClassModel()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_client.py b/samples/client/petstore/python-experimental/test/test_client.py
index 9e18c4310d96..ab5e3a80d377 100644
--- a/samples/client/petstore/python-experimental/test/test_client.py
+++ b/samples/client/petstore/python-experimental/test/test_client.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.client import Client  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.client import Client
 
 
 class TestClient(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testClient(self):
         """Test Client"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.client.Client()  # noqa: E501
+        # model = Client()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_dog.py b/samples/client/petstore/python-experimental/test/test_dog.py
index 91f9318b9c68..26949b34ae7f 100644
--- a/samples/client/petstore/python-experimental/test/test_dog.py
+++ b/samples/client/petstore/python-experimental/test/test_dog.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import animal
+except ImportError:
+    animal = sys.modules[
+        'petstore_api.model.animal']
+try:
+    from petstore_api.model import dog_all_of
+except ImportError:
+    dog_all_of = sys.modules[
+        'petstore_api.model.dog_all_of']
+from petstore_api.model.dog import Dog
 
 
 class TestDog(unittest.TestCase):
@@ -33,7 +44,7 @@ def testDog(self):
         class_name = 'Dog'
         color = 'white'
         breed = 'Jack Russel Terrier'
-        dog = petstore_api.Dog(
+        dog = Dog(
             class_name=class_name,
             color=color,
             breed=breed
@@ -87,8 +98,8 @@ def testDog(self):
             {
                 'anyOf': [],
                 'allOf': [
-                    petstore_api.Animal,
-                    petstore_api.DogAllOf,
+                    animal.Animal,
+                    dog_all_of.DogAllOf,
                 ],
                 'oneOf': [],
             }
@@ -96,9 +107,9 @@ def testDog(self):
         # model._composed_instances is a list of the instances that were
         # made from the anyOf/allOf/OneOf classes in model._composed_schemas()
         for composed_instance in dog._composed_instances:
-            if composed_instance.__class__ == petstore_api.Animal:
+            if composed_instance.__class__ == animal.Animal:
                 animal_instance = composed_instance
-            elif composed_instance.__class__ == petstore_api.DogAllOf:
+            elif composed_instance.__class__ == dog_all_of.DogAllOf:
                 dog_allof_instance = composed_instance
         self.assertEqual(
             dog._composed_instances,
@@ -129,13 +140,12 @@ def testDog(self):
 
         # including extra parameters raises an exception
         with self.assertRaises(petstore_api.ApiValueError):
-            dog = petstore_api.Dog(
+            dog = Dog(
                 class_name=class_name,
                 color=color,
                 breed=breed,
                 unknown_property='some value'
             )
 
-
 if __name__ == '__main__':
     unittest.main()
diff --git a/samples/client/petstore/python-experimental/test/test_dog_all_of.py b/samples/client/petstore/python-experimental/test/test_dog_all_of.py
index 3d79f2888c96..7ab4e8ae79d8 100644
--- a/samples/client/petstore/python-experimental/test/test_dog_all_of.py
+++ b/samples/client/petstore/python-experimental/test/test_dog_all_of.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.dog_all_of import DogAllOf  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.dog_all_of import DogAllOf
 
 
 class TestDogAllOf(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testDogAllOf(self):
         """Test DogAllOf"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.dog_all_of.DogAllOf()  # noqa: E501
+        # model = DogAllOf()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_enum_arrays.py b/samples/client/petstore/python-experimental/test/test_enum_arrays.py
index be572508ef22..64ad5fd7dc08 100644
--- a/samples/client/petstore/python-experimental/test/test_enum_arrays.py
+++ b/samples/client/petstore/python-experimental/test/test_enum_arrays.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.enum_arrays import EnumArrays  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.enum_arrays import EnumArrays
 
 
 class TestEnumArrays(unittest.TestCase):
@@ -28,12 +27,136 @@ def setUp(self):
     def tearDown(self):
         pass
 
-    def testEnumArrays(self):
-        """Test EnumArrays"""
-        # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.enum_arrays.EnumArrays()  # noqa: E501
-        pass
+    def test_enumarrays_init(self):
+        #
+        # Check various combinations of valid values.
+        #
+        fish_or_crab = EnumArrays(just_symbol=">=")
+        self.assertEqual(fish_or_crab.just_symbol, ">=")
+        # if optional property is unset we raise an exception
+        with self.assertRaises(petstore_api.ApiAttributeError) as exc:
+            self.assertEqual(fish_or_crab.array_enum, None)
+
+        fish_or_crab = EnumArrays(just_symbol="$", array_enum=["fish"])
+        self.assertEqual(fish_or_crab.just_symbol, "$")
+        self.assertEqual(fish_or_crab.array_enum, ["fish"])
+
+        fish_or_crab = EnumArrays(just_symbol=">=", array_enum=["fish"])
+        self.assertEqual(fish_or_crab.just_symbol, ">=")
+        self.assertEqual(fish_or_crab.array_enum, ["fish"])
+
+        fish_or_crab = EnumArrays(just_symbol="$", array_enum=["crab"])
+        self.assertEqual(fish_or_crab.just_symbol, "$")
+        self.assertEqual(fish_or_crab.array_enum, ["crab"])
+
+
+        #
+        # Check if setting invalid values fails
+        #
+        with self.assertRaises(petstore_api.ApiValueError) as exc:
+            fish_or_crab = EnumArrays(just_symbol="<=")
+
+        with self.assertRaises(petstore_api.ApiValueError) as exc:
+            fish_or_crab = EnumArrays(just_symbol="$", array_enum=["dog"])
+
+        with self.assertRaises(petstore_api.ApiTypeError) as exc:
+            fish_or_crab = EnumArrays(just_symbol=["$"], array_enum=["crab"])
+
+
+    def test_enumarrays_setter(self):
+
+        #
+        # Check various combinations of valid values
+        #
+        fish_or_crab = EnumArrays()
+
+        fish_or_crab.just_symbol = ">="
+        self.assertEqual(fish_or_crab.just_symbol, ">=")
+
+        fish_or_crab.just_symbol = "$"
+        self.assertEqual(fish_or_crab.just_symbol, "$")
+
+        fish_or_crab.array_enum = []
+        self.assertEqual(fish_or_crab.array_enum, [])
+
+        fish_or_crab.array_enum = ["fish"]
+        self.assertEqual(fish_or_crab.array_enum, ["fish"])
+
+        fish_or_crab.array_enum = ["fish", "fish", "fish"]
+        self.assertEqual(fish_or_crab.array_enum, ["fish", "fish", "fish"])
+
+        fish_or_crab.array_enum = ["crab"]
+        self.assertEqual(fish_or_crab.array_enum, ["crab"])
+
+        fish_or_crab.array_enum = ["crab", "fish"]
+        self.assertEqual(fish_or_crab.array_enum, ["crab", "fish"])
+
+        fish_or_crab.array_enum = ["crab", "fish", "crab", "fish"]
+        self.assertEqual(fish_or_crab.array_enum, ["crab", "fish", "crab", "fish"])
+
+        #
+        # Check if setting invalid values fails
+        #
+        fish_or_crab = EnumArrays()
+        with self.assertRaises(petstore_api.ApiValueError) as exc:
+            fish_or_crab.just_symbol = "!="
+
+        with self.assertRaises(petstore_api.ApiTypeError) as exc:
+            fish_or_crab.just_symbol = ["fish"]
+
+        with self.assertRaises(petstore_api.ApiValueError) as exc:
+            fish_or_crab.array_enum = ["cat"]
+
+        with self.assertRaises(petstore_api.ApiValueError) as exc:
+            fish_or_crab.array_enum = ["fish", "crab", "dog"]
+
+        with self.assertRaises(petstore_api.ApiTypeError) as exc:
+            fish_or_crab.array_enum = "fish"
+
+
+    def test_todict(self):
+        #
+        # Check if dictionary serialization works
+        #
+        dollar_fish_crab_dict = {
+            'just_symbol': "$",
+            'array_enum': ["fish", "crab"]
+        }
+
+        dollar_fish_crab = EnumArrays(
+            just_symbol="$", array_enum=["fish", "crab"])
+
+        self.assertEqual(dollar_fish_crab_dict, dollar_fish_crab.to_dict())
+
+        #
+        # Sanity check for different arrays
+        #
+        dollar_crab_fish_dict = {
+            'just_symbol': "$",
+            'array_enum': ["crab", "fish"]
+        }
+
+        dollar_fish_crab = EnumArrays(
+            just_symbol="$", array_enum=["fish", "crab"])
+
+        self.assertNotEqual(dollar_crab_fish_dict, dollar_fish_crab.to_dict())
+
+
+    def test_equals(self):
+        #
+        # Check if object comparison works
+        #
+        fish1 = EnumArrays(just_symbol="$", array_enum=["fish"])
+        fish2 = EnumArrays(just_symbol="$", array_enum=["fish"])
+        self.assertEqual(fish1, fish2)
+
+        fish = EnumArrays(just_symbol="$", array_enum=["fish"])
+        crab = EnumArrays(just_symbol="$", array_enum=["crab"])
+        self.assertNotEqual(fish, crab)
 
+        dollar = EnumArrays(just_symbol="$")
+        greater = EnumArrays(just_symbol=">=")
+        self.assertNotEqual(dollar, greater)
 
 if __name__ == '__main__':
     unittest.main()
diff --git a/samples/client/petstore/python-experimental/test/test_enum_class.py b/samples/client/petstore/python-experimental/test/test_enum_class.py
index 57eb14558a7d..f910231c9d02 100644
--- a/samples/client/petstore/python-experimental/test/test_enum_class.py
+++ b/samples/client/petstore/python-experimental/test/test_enum_class.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.enum_class import EnumClass  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.enum_class import EnumClass
 
 
 class TestEnumClass(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testEnumClass(self):
         """Test EnumClass"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.enum_class.EnumClass()  # noqa: E501
+        # model = EnumClass()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_enum_test.py b/samples/client/petstore/python-experimental/test/test_enum_test.py
index ecd43afc709d..0ada34cdc1f2 100644
--- a/samples/client/petstore/python-experimental/test/test_enum_test.py
+++ b/samples/client/petstore/python-experimental/test/test_enum_test.py
@@ -5,18 +5,22 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.enum_test import EnumTest  # noqa: E501
-from petstore_api.rest import ApiException
+try:
+    from petstore_api.model import outer_enum
+except ImportError:
+    outer_enum = sys.modules[
+        'petstore_api.model.outer_enum']
+from petstore_api.model.enum_test import EnumTest
 
 
 class TestEnumTest(unittest.TestCase):
@@ -31,7 +35,7 @@ def tearDown(self):
     def testEnumTest(self):
         """Test EnumTest"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.enum_test.EnumTest()  # noqa: E501
+        # model = EnumTest()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_fake_api.py b/samples/client/petstore/python-experimental/test/test_fake_api.py
index 7a6f1d6810a0..d55e538b8608 100644
--- a/samples/client/petstore/python-experimental/test/test_fake_api.py
+++ b/samples/client/petstore/python-experimental/test/test_fake_api.py
@@ -11,24 +11,18 @@
 
 
 from __future__ import absolute_import
-import six
 
 import unittest
-if six.PY3:
-    from unittest.mock import patch
-else:
-    from mock import patch
 
 import petstore_api
 from petstore_api.api.fake_api import FakeApi  # noqa: E501
-from petstore_api.rest import ApiException
 
 
 class TestFakeApi(unittest.TestCase):
     """FakeApi unit test stubs"""
 
     def setUp(self):
-        self.api = petstore_api.api.fake_api.FakeApi()  # noqa: E501
+        self.api = FakeApi()  # noqa: E501
 
     def tearDown(self):
         pass
@@ -57,18 +51,20 @@ def test_fake_outer_enum_serialize(self):
 
         """
         # verify that the input and output are type OuterEnum
+        from petstore_api.model import outer_enum
         endpoint = self.api.fake_outer_enum_serialize
-        assert endpoint.openapi_types['body'] == (petstore_api.OuterEnum,)
-        assert endpoint.settings['response_type'] == (petstore_api.OuterEnum,)
+        assert endpoint.openapi_types['body'] == (outer_enum.OuterEnum,)
+        assert endpoint.settings['response_type'] == (outer_enum.OuterEnum,)
 
     def test_fake_outer_number_serialize(self):
         """Test case for fake_outer_number_serialize
 
         """
         # verify that the input and output are the correct type
+        from petstore_api.model import outer_number
         endpoint = self.api.fake_outer_number_serialize
-        assert endpoint.openapi_types['body'] == (petstore_api.OuterNumber,)
-        assert endpoint.settings['response_type'] == (petstore_api.OuterNumber,)
+        assert endpoint.openapi_types['body'] == (outer_number.OuterNumber,)
+        assert endpoint.settings['response_type'] == (outer_number.OuterNumber,)
 
     def test_fake_outer_string_serialize(self):
         """Test case for fake_outer_string_serialize
@@ -101,6 +97,11 @@ def test_test_endpoint_enums_length_one(self):
         """
         # when we omit the required enums of length one, they are still set
         endpoint = self.api.test_endpoint_enums_length_one
+        import six
+        if six.PY3:
+            from unittest.mock import patch
+        else:
+            from mock import patch
         with patch.object(endpoint, 'call_with_http_info') as call_with_http_info:
             endpoint()
             call_with_http_info.assert_called_with(
diff --git a/samples/client/petstore/python-experimental/test/test_fake_classname_tags_123_api.py b/samples/client/petstore/python-experimental/test/test_fake_classname_tags_123_api.py
index 87cac0b9ef85..1ade31405a62 100644
--- a/samples/client/petstore/python-experimental/test/test_fake_classname_tags_123_api.py
+++ b/samples/client/petstore/python-experimental/test/test_fake_classname_tags_123_api.py
@@ -5,25 +5,24 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
 from petstore_api.api.fake_classname_tags_123_api import FakeClassnameTags123Api  # noqa: E501
-from petstore_api.rest import ApiException
 
 
 class TestFakeClassnameTags123Api(unittest.TestCase):
     """FakeClassnameTags123Api unit test stubs"""
 
     def setUp(self):
-        self.api = petstore_api.api.fake_classname_tags_123_api.FakeClassnameTags123Api()  # noqa: E501
+        self.api = FakeClassnameTags123Api()  # noqa: E501
 
     def tearDown(self):
         pass
diff --git a/samples/client/petstore/python-experimental/test/test_file.py b/samples/client/petstore/python-experimental/test/test_file.py
index cc32edb7b523..8d60f64e01cc 100644
--- a/samples/client/petstore/python-experimental/test/test_file.py
+++ b/samples/client/petstore/python-experimental/test/test_file.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.file import File  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.file import File
 
 
 class TestFile(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testFile(self):
         """Test File"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.file.File()  # noqa: E501
+        # model = File()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_file_schema_test_class.py b/samples/client/petstore/python-experimental/test/test_file_schema_test_class.py
index 91e1b6a1c745..9a4f6d38dfef 100644
--- a/samples/client/petstore/python-experimental/test/test_file_schema_test_class.py
+++ b/samples/client/petstore/python-experimental/test/test_file_schema_test_class.py
@@ -5,18 +5,22 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.file_schema_test_class import FileSchemaTestClass  # noqa: E501
-from petstore_api.rest import ApiException
+try:
+    from petstore_api.model import file
+except ImportError:
+    file = sys.modules[
+        'petstore_api.model.file']
+from petstore_api.model.file_schema_test_class import FileSchemaTestClass
 
 
 class TestFileSchemaTestClass(unittest.TestCase):
@@ -31,7 +35,7 @@ def tearDown(self):
     def testFileSchemaTestClass(self):
         """Test FileSchemaTestClass"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.file_schema_test_class.FileSchemaTestClass()  # noqa: E501
+        # model = FileSchemaTestClass()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_format_test.py b/samples/client/petstore/python-experimental/test/test_format_test.py
index e7a32e3253ff..ca37b005fd96 100644
--- a/samples/client/petstore/python-experimental/test/test_format_test.py
+++ b/samples/client/petstore/python-experimental/test/test_format_test.py
@@ -2,26 +2,27 @@
 
 """
     OpenAPI Petstore
+
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
-    OpenAPI spec version: 1.0.0
+
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
-import datetime
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.format_test import FormatTest  # noqa: E501
-from petstore_api import ApiValueError
+from petstore_api.model.format_test import FormatTest
 
 
 class TestFormatTest(unittest.TestCase):
     """FormatTest unit test stubs"""
 
     def setUp(self):
+        import datetime
         self.required_named_args = dict(
             number=40.1,
             byte='what',
@@ -37,7 +38,7 @@ def test_integer(self):
         key_adder_pairs = [('inclusive_maximum', 1), ('inclusive_minimum', -1)]
         for key, adder in key_adder_pairs:
             # value outside the bounds throws an error
-            with self.assertRaises(ApiValueError):
+            with self.assertRaises(petstore_api.ApiValueError):
                 keyword_args[var_name] = validations[key] + adder
                 FormatTest(**keyword_args)
 
@@ -54,7 +55,7 @@ def test_int32(self):
         key_adder_pairs = [('inclusive_maximum', 1), ('inclusive_minimum', -1)]
         for key, adder in key_adder_pairs:
             # value outside the bounds throws an error
-            with self.assertRaises(ApiValueError):
+            with self.assertRaises(petstore_api.ApiValueError):
                 keyword_args[var_name] = validations[key] + adder
                 FormatTest(**keyword_args)
 
@@ -71,7 +72,7 @@ def test_number(self):
         key_adder_pairs = [('inclusive_maximum', 1), ('inclusive_minimum', -1)]
         for key, adder in key_adder_pairs:
             # value outside the bounds throws an error
-            with self.assertRaises(ApiValueError):
+            with self.assertRaises(petstore_api.ApiValueError):
                 keyword_args[var_name] = validations[key] + adder
                 FormatTest(**keyword_args)
 
@@ -88,7 +89,7 @@ def test_float(self):
         key_adder_pairs = [('inclusive_maximum', 1), ('inclusive_minimum', -1)]
         for key, adder in key_adder_pairs:
             # value outside the bounds throws an error
-            with self.assertRaises(ApiValueError):
+            with self.assertRaises(petstore_api.ApiValueError):
                 keyword_args[var_name] = validations[key] + adder
                 FormatTest(**keyword_args)
 
@@ -105,7 +106,7 @@ def test_double(self):
         key_adder_pairs = [('inclusive_maximum', 1), ('inclusive_minimum', -1)]
         for key, adder in key_adder_pairs:
             # value outside the bounds throws an error
-            with self.assertRaises(ApiValueError):
+            with self.assertRaises(petstore_api.ApiValueError):
                 keyword_args[var_name] = validations[key] + adder
                 FormatTest(**keyword_args)
 
@@ -122,7 +123,7 @@ def test_password(self):
         key_adder_pairs = [('max_length', 1), ('min_length', -1)]
         for key, adder in key_adder_pairs:
             # value outside the bounds throws an error
-            with self.assertRaises(ApiValueError):
+            with self.assertRaises(petstore_api.ApiValueError):
                 keyword_args[var_name] = 'a'*(validations[key] + adder)
                 FormatTest(**keyword_args)
 
@@ -139,7 +140,7 @@ def test_string(self):
         values_invalid = ['abc3', '1', '.', ' ', 'مرحبا', '']
         for value_invalid in values_invalid:
             # invalid values throw exceptions
-            with self.assertRaises(ApiValueError):
+            with self.assertRaises(petstore_api.ApiValueError):
                 keyword_args[var_name] = value_invalid
                 FormatTest(**keyword_args)
 
@@ -148,6 +149,5 @@ def test_string(self):
         keyword_args[var_name] = value_valid
         assert getattr(FormatTest(**keyword_args), var_name) == value_valid
 
-
 if __name__ == '__main__':
     unittest.main()
diff --git a/samples/client/petstore/python-experimental/test/test_grandparent.py b/samples/client/petstore/python-experimental/test/test_grandparent.py
index 44f594c086e4..2972d01161cd 100644
--- a/samples/client/petstore/python-experimental/test/test_grandparent.py
+++ b/samples/client/petstore/python-experimental/test/test_grandparent.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.grandparent import Grandparent
 
 
 class TestGrandparent(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testGrandparent(self):
         """Test Grandparent"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Grandparent()  # noqa: E501
+        # model = Grandparent()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_grandparent_animal.py b/samples/client/petstore/python-experimental/test/test_grandparent_animal.py
index dc0d300cdaea..cabe4d81f98e 100644
--- a/samples/client/petstore/python-experimental/test/test_grandparent_animal.py
+++ b/samples/client/petstore/python-experimental/test/test_grandparent_animal.py
@@ -11,10 +11,31 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import child_cat
+except ImportError:
+    child_cat = sys.modules[
+        'petstore_api.model.child_cat']
+try:
+    from petstore_api.model import child_dog
+except ImportError:
+    child_dog = sys.modules[
+        'petstore_api.model.child_dog']
+try:
+    from petstore_api.model import child_lizard
+except ImportError:
+    child_lizard = sys.modules[
+        'petstore_api.model.child_lizard']
+try:
+    from petstore_api.model import parent_pet
+except ImportError:
+    parent_pet = sys.modules[
+        'petstore_api.model.parent_pet']
+from petstore_api.model.grandparent_animal import GrandparentAnimal
 
 
 class TestGrandparentAnimal(unittest.TestCase):
@@ -29,7 +50,7 @@ def tearDown(self):
     def testGrandparentAnimal(self):
         """Test GrandparentAnimal"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.GrandparentAnimal()  # noqa: E501
+        # model = GrandparentAnimal()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_has_only_read_only.py b/samples/client/petstore/python-experimental/test/test_has_only_read_only.py
index 2dc052a328a0..9ebd7683b398 100644
--- a/samples/client/petstore/python-experimental/test/test_has_only_read_only.py
+++ b/samples/client/petstore/python-experimental/test/test_has_only_read_only.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.has_only_read_only import HasOnlyReadOnly  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.has_only_read_only import HasOnlyReadOnly
 
 
 class TestHasOnlyReadOnly(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testHasOnlyReadOnly(self):
         """Test HasOnlyReadOnly"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.has_only_read_only.HasOnlyReadOnly()  # noqa: E501
+        # model = HasOnlyReadOnly()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_list.py b/samples/client/petstore/python-experimental/test/test_list.py
index a538a6b1ad36..52156adfed2e 100644
--- a/samples/client/petstore/python-experimental/test/test_list.py
+++ b/samples/client/petstore/python-experimental/test/test_list.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.list import List  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.list import List
 
 
 class TestList(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testList(self):
         """Test List"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.list.List()  # noqa: E501
+        # model = List()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_map_test.py b/samples/client/petstore/python-experimental/test/test_map_test.py
index 0ba6481903e6..3feda0f688df 100644
--- a/samples/client/petstore/python-experimental/test/test_map_test.py
+++ b/samples/client/petstore/python-experimental/test/test_map_test.py
@@ -5,18 +5,22 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.map_test import MapTest  # noqa: E501
-from petstore_api.rest import ApiException
+try:
+    from petstore_api.model import string_boolean_map
+except ImportError:
+    string_boolean_map = sys.modules[
+        'petstore_api.model.string_boolean_map']
+from petstore_api.model.map_test import MapTest
 
 
 class TestMapTest(unittest.TestCase):
@@ -28,12 +32,94 @@ def setUp(self):
     def tearDown(self):
         pass
 
-    def testMapTest(self):
-        """Test MapTest"""
-        # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.map_test.MapTest()  # noqa: E501
-        pass
+    def test_maptest_init(self):
+        #
+        # Test MapTest construction with valid values
+        #
+        up_or_low_dict = {
+            'UPPER': "UP",
+            'lower': "low"
+        }
+        map_enum_test = MapTest(map_of_enum_string=up_or_low_dict)
+
+        self.assertEqual(map_enum_test.map_of_enum_string, up_or_low_dict)
+
+        map_of_map_of_strings = {
+            'valueDict': up_or_low_dict
+        }
+        map_enum_test = MapTest(map_map_of_string=map_of_map_of_strings)
+
+        self.assertEqual(map_enum_test.map_map_of_string, map_of_map_of_strings)
+
+        #
+        # Make sure that the init fails for invalid enum values
+        #
+        black_or_white_dict = {
+            'black': "UP",
+            'white': "low"
+        }
+        with self.assertRaises(petstore_api.ApiValueError):
+            MapTest(map_of_enum_string=black_or_white_dict)
+
+    def test_maptest_setter(self):
+        #
+        # Check with some valid values
+        #
+        map_enum_test = MapTest()
+        up_or_low_dict = {
+            'UPPER': "UP",
+            'lower': "low"
+        }
+        map_enum_test.map_of_enum_string = up_or_low_dict
+        self.assertEqual(map_enum_test.map_of_enum_string, up_or_low_dict)
+
+        #
+        # Check if the setter fails for invalid enum values
+        #
+        map_enum_test = MapTest()
+        black_or_white_dict = {
+            'black': "UP",
+            'white': "low"
+        }
+        with self.assertRaises(petstore_api.ApiValueError):
+            map_enum_test.map_of_enum_string = black_or_white_dict
+
+    def test_todict(self):
+        #
+        # Check dictionary serialization
+        #
+        map_enum_test = MapTest()
+        up_or_low_dict = {
+            'UPPER': "UP",
+            'lower': "low"
+        }
+        map_of_map_of_strings = {
+            'valueDict': up_or_low_dict
+        }
+        indirect_map = string_boolean_map.StringBooleanMap(**{
+            'option1': True
+        })
+        direct_map = {
+            'option2': False
+        }
+        map_enum_test.map_of_enum_string = up_or_low_dict
+        map_enum_test.map_map_of_string = map_of_map_of_strings
+        map_enum_test.indirect_map = indirect_map
+        map_enum_test.direct_map = direct_map
+
+        self.assertEqual(map_enum_test.map_of_enum_string, up_or_low_dict)
+        self.assertEqual(map_enum_test.map_map_of_string, map_of_map_of_strings)
+        self.assertEqual(map_enum_test.indirect_map, indirect_map)
+        self.assertEqual(map_enum_test.direct_map, direct_map)
+
+        expected_dict = {
+            'map_of_enum_string': up_or_low_dict,
+            'map_map_of_string': map_of_map_of_strings,
+            'indirect_map': indirect_map.to_dict(),
+            'direct_map': direct_map
+        }
 
+        self.assertEqual(map_enum_test.to_dict(), expected_dict)
 
 if __name__ == '__main__':
     unittest.main()
diff --git a/samples/client/petstore/python-experimental/test/test_mixed_properties_and_additional_properties_class.py b/samples/client/petstore/python-experimental/test/test_mixed_properties_and_additional_properties_class.py
index 8893bdaf44ee..4dcb5ad4268c 100644
--- a/samples/client/petstore/python-experimental/test/test_mixed_properties_and_additional_properties_class.py
+++ b/samples/client/petstore/python-experimental/test/test_mixed_properties_and_additional_properties_class.py
@@ -5,18 +5,22 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.mixed_properties_and_additional_properties_class import MixedPropertiesAndAdditionalPropertiesClass  # noqa: E501
-from petstore_api.rest import ApiException
+try:
+    from petstore_api.model import animal
+except ImportError:
+    animal = sys.modules[
+        'petstore_api.model.animal']
+from petstore_api.model.mixed_properties_and_additional_properties_class import MixedPropertiesAndAdditionalPropertiesClass
 
 
 class TestMixedPropertiesAndAdditionalPropertiesClass(unittest.TestCase):
@@ -31,7 +35,7 @@ def tearDown(self):
     def testMixedPropertiesAndAdditionalPropertiesClass(self):
         """Test MixedPropertiesAndAdditionalPropertiesClass"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.mixed_properties_and_additional_properties_class.MixedPropertiesAndAdditionalPropertiesClass()  # noqa: E501
+        # model = MixedPropertiesAndAdditionalPropertiesClass()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_model200_response.py b/samples/client/petstore/python-experimental/test/test_model200_response.py
index fab761f4edba..4012eaae3362 100644
--- a/samples/client/petstore/python-experimental/test/test_model200_response.py
+++ b/samples/client/petstore/python-experimental/test/test_model200_response.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.model200_response import Model200Response  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.model200_response import Model200Response
 
 
 class TestModel200Response(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testModel200Response(self):
         """Test Model200Response"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.model200_response.Model200Response()  # noqa: E501
+        # model = Model200Response()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_model_return.py b/samples/client/petstore/python-experimental/test/test_model_return.py
index ae3f15ee6b83..54c98b33cd66 100644
--- a/samples/client/petstore/python-experimental/test/test_model_return.py
+++ b/samples/client/petstore/python-experimental/test/test_model_return.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.model_return import ModelReturn  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.model_return import ModelReturn
 
 
 class TestModelReturn(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testModelReturn(self):
         """Test ModelReturn"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.model_return.ModelReturn()  # noqa: E501
+        # model = ModelReturn()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_name.py b/samples/client/petstore/python-experimental/test/test_name.py
index d6c72563991f..6a9be99d1a57 100644
--- a/samples/client/petstore/python-experimental/test/test_name.py
+++ b/samples/client/petstore/python-experimental/test/test_name.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.name import Name  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.name import Name
 
 
 class TestName(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testName(self):
         """Test Name"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.name.Name()  # noqa: E501
+        # model = Name()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_number_only.py b/samples/client/petstore/python-experimental/test/test_number_only.py
index 7f6df65c8058..07aab1d78af7 100644
--- a/samples/client/petstore/python-experimental/test/test_number_only.py
+++ b/samples/client/petstore/python-experimental/test/test_number_only.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.number_only import NumberOnly  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.number_only import NumberOnly
 
 
 class TestNumberOnly(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testNumberOnly(self):
         """Test NumberOnly"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.number_only.NumberOnly()  # noqa: E501
+        # model = NumberOnly()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_order.py b/samples/client/petstore/python-experimental/test/test_order.py
index 3e7d517d5c79..ee6988e28ccd 100644
--- a/samples/client/petstore/python-experimental/test/test_order.py
+++ b/samples/client/petstore/python-experimental/test/test_order.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.order import Order  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.order import Order
 
 
 class TestOrder(unittest.TestCase):
@@ -30,9 +29,12 @@ def tearDown(self):
 
     def testOrder(self):
         """Test Order"""
-        # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.order.Order()  # noqa: E501
-        pass
+        order = Order()
+        order.status = "placed"
+        self.assertEqual("placed", order.status)
+        with self.assertRaises(petstore_api.ApiValueError):
+            order.status = "invalid"
+
 
 
 if __name__ == '__main__':
diff --git a/samples/client/petstore/python-experimental/test/test_outer_composite.py b/samples/client/petstore/python-experimental/test/test_outer_composite.py
index dcb078cd2164..f3ad1beff9e4 100644
--- a/samples/client/petstore/python-experimental/test/test_outer_composite.py
+++ b/samples/client/petstore/python-experimental/test/test_outer_composite.py
@@ -5,18 +5,22 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.outer_composite import OuterComposite  # noqa: E501
-from petstore_api.rest import ApiException
+try:
+    from petstore_api.model import outer_number
+except ImportError:
+    outer_number = sys.modules[
+        'petstore_api.model.outer_number']
+from petstore_api.model.outer_composite import OuterComposite
 
 
 class TestOuterComposite(unittest.TestCase):
@@ -31,7 +35,7 @@ def tearDown(self):
     def testOuterComposite(self):
         """Test OuterComposite"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.outer_composite.OuterComposite()  # noqa: E501
+        # model = OuterComposite()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_outer_enum.py b/samples/client/petstore/python-experimental/test/test_outer_enum.py
index 50bfff0869b7..ff84ad3ba6d4 100644
--- a/samples/client/petstore/python-experimental/test/test_outer_enum.py
+++ b/samples/client/petstore/python-experimental/test/test_outer_enum.py
@@ -11,12 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.outer_enum import OuterEnum  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.outer_enum import OuterEnum
 
 
 class TestOuterEnum(unittest.TestCase):
@@ -43,5 +42,6 @@ def testOuterEnum(self):
         valid_value = OuterEnum.allowed_values[('value',)]['PLACED']
         assert valid_value == OuterEnum(valid_value).value
 
+
 if __name__ == '__main__':
     unittest.main()
diff --git a/samples/client/petstore/python-experimental/test/test_outer_number.py b/samples/client/petstore/python-experimental/test/test_outer_number.py
index 31c9c41755dc..e0ab10d91d61 100644
--- a/samples/client/petstore/python-experimental/test/test_outer_number.py
+++ b/samples/client/petstore/python-experimental/test/test_outer_number.py
@@ -11,12 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.outer_number import OuterNumber  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.outer_number import OuterNumber
 
 
 class TestOuterNumber(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testOuterNumber(self):
         """Test OuterNumber"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.outer_number.OuterNumber()  # noqa: E501
+        # model = OuterNumber()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_parent.py b/samples/client/petstore/python-experimental/test/test_parent.py
index f719771bdcfb..20282dfb41ea 100644
--- a/samples/client/petstore/python-experimental/test/test_parent.py
+++ b/samples/client/petstore/python-experimental/test/test_parent.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import grandparent
+except ImportError:
+    grandparent = sys.modules[
+        'petstore_api.model.grandparent']
+try:
+    from petstore_api.model import parent_all_of
+except ImportError:
+    parent_all_of = sys.modules[
+        'petstore_api.model.parent_all_of']
+from petstore_api.model.parent import Parent
 
 
 class TestParent(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testParent(self):
         """Test Parent"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Parent()  # noqa: E501
+        # model = Parent()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_parent_all_of.py b/samples/client/petstore/python-experimental/test/test_parent_all_of.py
index c1c152afe18a..ca87189bba50 100644
--- a/samples/client/petstore/python-experimental/test/test_parent_all_of.py
+++ b/samples/client/petstore/python-experimental/test/test_parent_all_of.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.parent_all_of import ParentAllOf
 
 
 class TestParentAllOf(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testParentAllOf(self):
         """Test ParentAllOf"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ParentAllOf()  # noqa: E501
+        # model = ParentAllOf()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_parent_pet.py b/samples/client/petstore/python-experimental/test/test_parent_pet.py
index b3ec1a94532c..17a4d60e75dc 100644
--- a/samples/client/petstore/python-experimental/test/test_parent_pet.py
+++ b/samples/client/petstore/python-experimental/test/test_parent_pet.py
@@ -11,10 +11,31 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import child_cat
+except ImportError:
+    child_cat = sys.modules[
+        'petstore_api.model.child_cat']
+try:
+    from petstore_api.model import child_dog
+except ImportError:
+    child_dog = sys.modules[
+        'petstore_api.model.child_dog']
+try:
+    from petstore_api.model import child_lizard
+except ImportError:
+    child_lizard = sys.modules[
+        'petstore_api.model.child_lizard']
+try:
+    from petstore_api.model import grandparent_animal
+except ImportError:
+    grandparent_animal = sys.modules[
+        'petstore_api.model.grandparent_animal']
+from petstore_api.model.parent_pet import ParentPet
 
 
 class TestParentPet(unittest.TestCase):
@@ -29,7 +50,7 @@ def tearDown(self):
     def testParentPet(self):
         """Test ParentPet"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ParentPet()  # noqa: E501
+        # model = ParentPet()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_pet.py b/samples/client/petstore/python-experimental/test/test_pet.py
index bc5cc30fac0d..b072cff5e9ad 100644
--- a/samples/client/petstore/python-experimental/test/test_pet.py
+++ b/samples/client/petstore/python-experimental/test/test_pet.py
@@ -5,18 +5,27 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.pet import Pet  # noqa: E501
-from petstore_api.rest import ApiException
+try:
+    from petstore_api.model import category
+except ImportError:
+    category = sys.modules[
+        'petstore_api.model.category']
+try:
+    from petstore_api.models import tag
+except ImportError:
+    tag = sys.modules[
+        'petstore_api.model.tag']
+from petstore_api.model.pet import Pet
 
 
 class TestPet(unittest.TestCase):
@@ -28,11 +37,52 @@ def setUp(self):
     def tearDown(self):
         pass
 
-    def testPet(self):
-        """Test Pet"""
-        # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.pet.Pet()  # noqa: E501
-        pass
+    def test_to_str(self):
+        pet = Pet(name="test name", photo_urls=["string"])
+        pet.id = 1
+        pet.status = "available"
+        cate = category.Category()
+        cate.id = 1
+        cate.name = "dog"
+        pet.category = cate
+        tag1 = tag.Tag()
+        tag1.id = 1
+        pet.tags = [tag1]
+
+        data = ("{'category': {'id': 1, 'name': 'dog'},\n"
+                " 'id': 1,\n"
+                " 'name': 'test name',\n"
+                " 'photo_urls': ['string'],\n"
+                " 'status': 'available',\n"
+                " 'tags': [{'id': 1}]}")
+        self.assertEqual(data, pet.to_str())
+
+    def test_equal(self):
+        pet1 = Pet(name="test name", photo_urls=["string"])
+        pet1.id = 1
+        pet1.status = "available"
+        cate1 = category.Category()
+        cate1.id = 1
+        cate1.name = "dog"
+        tag1 = tag.Tag()
+        tag1.id = 1
+        pet1.tags = [tag1]
+
+        pet2 = Pet(name="test name", photo_urls=["string"])
+        pet2.id = 1
+        pet2.status = "available"
+        cate2 = category.Category()
+        cate2.id = 1
+        cate2.name = "dog"
+        tag2 = tag.Tag()
+        tag2.id = 1
+        pet2.tags = [tag2]
+
+        self.assertTrue(pet1 == pet2)
+
+        # reset pet1 tags to empty array so that object comparison returns false
+        pet1.tags = []
+        self.assertFalse(pet1 == pet2)
 
 
 if __name__ == '__main__':
diff --git a/samples/client/petstore/python-experimental/test/test_pet_api.py b/samples/client/petstore/python-experimental/test/test_pet_api.py
index ffd3e25c4c64..091b30cf8ac0 100644
--- a/samples/client/petstore/python-experimental/test/test_pet_api.py
+++ b/samples/client/petstore/python-experimental/test/test_pet_api.py
@@ -5,25 +5,24 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
 from petstore_api.api.pet_api import PetApi  # noqa: E501
-from petstore_api.rest import ApiException
 
 
 class TestPetApi(unittest.TestCase):
     """PetApi unit test stubs"""
 
     def setUp(self):
-        self.api = petstore_api.api.pet_api.PetApi()  # noqa: E501
+        self.api = PetApi()  # noqa: E501
 
     def tearDown(self):
         pass
@@ -84,6 +83,13 @@ def test_upload_file(self):
         """
         pass
 
+    def test_upload_file_with_required_file(self):
+        """Test case for upload_file_with_required_file
+
+        uploads an image (required)  # noqa: E501
+        """
+        pass
+
 
 if __name__ == '__main__':
     unittest.main()
diff --git a/samples/client/petstore/python-experimental/test/test_player.py b/samples/client/petstore/python-experimental/test/test_player.py
index b100dd798943..ee7b95a677f1 100644
--- a/samples/client/petstore/python-experimental/test/test_player.py
+++ b/samples/client/petstore/python-experimental/test/test_player.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.player import Player
 
 
 class TestPlayer(unittest.TestCase):
@@ -29,13 +30,13 @@ def tearDown(self):
     def testPlayer(self):
         """Test Player"""
         # we can make a player without an enemy_player property
-        jane = petstore_api.Player(name="Jane")
+        jane = Player(name="Jane")
         # we can make a player with an enemy_player
-        sally = petstore_api.Player(name="Sally", enemy_player=jane)
+        sally = Player(name="Sally", enemy_player=jane)
         # we can make a player with an inline enemy_player
-        jim = petstore_api.Player(
+        jim = Player(
             name="Jim",
-            enemy_player=petstore_api.Player(name="Sam")
+            enemy_player=Player(name="Sam")
         )
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_read_only_first.py b/samples/client/petstore/python-experimental/test/test_read_only_first.py
index 2b647b83fc89..c2dcde240e77 100644
--- a/samples/client/petstore/python-experimental/test/test_read_only_first.py
+++ b/samples/client/petstore/python-experimental/test/test_read_only_first.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.read_only_first import ReadOnlyFirst  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.read_only_first import ReadOnlyFirst
 
 
 class TestReadOnlyFirst(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testReadOnlyFirst(self):
         """Test ReadOnlyFirst"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.read_only_first.ReadOnlyFirst()  # noqa: E501
+        # model = ReadOnlyFirst()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_special_model_name.py b/samples/client/petstore/python-experimental/test/test_special_model_name.py
index 4edfec164f7d..6124525f5170 100644
--- a/samples/client/petstore/python-experimental/test/test_special_model_name.py
+++ b/samples/client/petstore/python-experimental/test/test_special_model_name.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.special_model_name import SpecialModelName  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.special_model_name import SpecialModelName
 
 
 class TestSpecialModelName(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testSpecialModelName(self):
         """Test SpecialModelName"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.special_model_name.SpecialModelName()  # noqa: E501
+        # model = SpecialModelName()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_store_api.py b/samples/client/petstore/python-experimental/test/test_store_api.py
index 37bf771d13a6..0d9cc3dd36ea 100644
--- a/samples/client/petstore/python-experimental/test/test_store_api.py
+++ b/samples/client/petstore/python-experimental/test/test_store_api.py
@@ -5,7 +5,7 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
@@ -16,14 +16,13 @@
 
 import petstore_api
 from petstore_api.api.store_api import StoreApi  # noqa: E501
-from petstore_api.rest import ApiException
 
 
 class TestStoreApi(unittest.TestCase):
     """StoreApi unit test stubs"""
 
     def setUp(self):
-        self.api = petstore_api.api.store_api.StoreApi()  # noqa: E501
+        self.api = StoreApi()  # noqa: E501
 
     def tearDown(self):
         pass
diff --git a/samples/client/petstore/python-experimental/test/test_string_boolean_map.py b/samples/client/petstore/python-experimental/test/test_string_boolean_map.py
index 31c1ebeec5db..e2e9d8b420b8 100644
--- a/samples/client/petstore/python-experimental/test/test_string_boolean_map.py
+++ b/samples/client/petstore/python-experimental/test/test_string_boolean_map.py
@@ -11,12 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.string_boolean_map import StringBooleanMap  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.string_boolean_map import StringBooleanMap
 
 
 class TestStringBooleanMap(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testStringBooleanMap(self):
         """Test StringBooleanMap"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.string_boolean_map.StringBooleanMap()  # noqa: E501
+        # model = StringBooleanMap()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_tag.py b/samples/client/petstore/python-experimental/test/test_tag.py
index 2c3c5157e718..68a3b9046bf4 100644
--- a/samples/client/petstore/python-experimental/test/test_tag.py
+++ b/samples/client/petstore/python-experimental/test/test_tag.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.tag import Tag  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.tag import Tag
 
 
 class TestTag(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testTag(self):
         """Test Tag"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.tag.Tag()  # noqa: E501
+        # model = Tag()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_type_holder_default.py b/samples/client/petstore/python-experimental/test/test_type_holder_default.py
index 08a201b854d0..f9c050b81a82 100644
--- a/samples/client/petstore/python-experimental/test/test_type_holder_default.py
+++ b/samples/client/petstore/python-experimental/test/test_type_holder_default.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.type_holder_default import TypeHolderDefault  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.type_holder_default import TypeHolderDefault
 
 
 class TestTypeHolderDefault(unittest.TestCase):
diff --git a/samples/client/petstore/python-experimental/test/test_type_holder_example.py b/samples/client/petstore/python-experimental/test/test_type_holder_example.py
index 7a2621494857..e1ee7c368628 100644
--- a/samples/client/petstore/python-experimental/test/test_type_holder_example.py
+++ b/samples/client/petstore/python-experimental/test/test_type_holder_example.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.type_holder_example import TypeHolderExample  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.type_holder_example import TypeHolderExample
 
 
 class TestTypeHolderExample(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testTypeHolderExample(self):
         """Test TypeHolderExample"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.type_holder_example.TypeHolderExample()  # noqa: E501
+        # model = TypeHolderExample()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_user.py b/samples/client/petstore/python-experimental/test/test_user.py
index ad9386b6908e..7241bb589c52 100644
--- a/samples/client/petstore/python-experimental/test/test_user.py
+++ b/samples/client/petstore/python-experimental/test/test_user.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.user import User  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.user import User
 
 
 class TestUser(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testUser(self):
         """Test User"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.user.User()  # noqa: E501
+        # model = User()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/test/test_user_api.py b/samples/client/petstore/python-experimental/test/test_user_api.py
index 6e8aed4f18c7..df306da07761 100644
--- a/samples/client/petstore/python-experimental/test/test_user_api.py
+++ b/samples/client/petstore/python-experimental/test/test_user_api.py
@@ -5,7 +5,7 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
@@ -16,14 +16,13 @@
 
 import petstore_api
 from petstore_api.api.user_api import UserApi  # noqa: E501
-from petstore_api.rest import ApiException
 
 
 class TestUserApi(unittest.TestCase):
     """UserApi unit test stubs"""
 
     def setUp(self):
-        self.api = petstore_api.api.user_api.UserApi()  # noqa: E501
+        self.api = UserApi()  # noqa: E501
 
     def tearDown(self):
         pass
diff --git a/samples/client/petstore/python-experimental/test/test_xml_item.py b/samples/client/petstore/python-experimental/test/test_xml_item.py
index 121f1ccb6623..4354664815ff 100644
--- a/samples/client/petstore/python-experimental/test/test_xml_item.py
+++ b/samples/client/petstore/python-experimental/test/test_xml_item.py
@@ -5,18 +5,17 @@
 
     This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
 
-    OpenAPI spec version: 1.0.0
+    The version of the OpenAPI document: 1.0.0
     Generated by: https://openapi-generator.tech
 """
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
-from petstore_api.models.xml_item import XmlItem  # noqa: E501
-from petstore_api.rest import ApiException
+from petstore_api.model.xml_item import XmlItem
 
 
 class TestXmlItem(unittest.TestCase):
@@ -31,7 +30,7 @@ def tearDown(self):
     def testXmlItem(self):
         """Test XmlItem"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.models.xml_item.XmlItem()  # noqa: E501
+        # model = XmlItem()  # noqa: E501
         pass
 
 
diff --git a/samples/client/petstore/python-experimental/tests/test_api_client.py b/samples/client/petstore/python-experimental/tests/test_api_client.py
index f36762e84e8e..c249bf1fc5e8 100644
--- a/samples/client/petstore/python-experimental/tests/test_api_client.py
+++ b/samples/client/petstore/python-experimental/tests/test_api_client.py
@@ -171,16 +171,20 @@ def test_sanitize_for_serialization(self):
                     "status": "available",
                     "photoUrls": ["http://foo.bar.com/3",
                                   "http://foo.bar.com/4"]}
-        pet = petstore_api.Pet(name=pet_dict["name"], photo_urls=pet_dict["photoUrls"])
+        from petstore_api.model.pet import Pet
+        from petstore_api.model.category import Category
+        from petstore_api.model.tag import Tag
+        from petstore_api.model.string_boolean_map import StringBooleanMap
+        pet = Pet(name=pet_dict["name"], photo_urls=pet_dict["photoUrls"])
         pet.id = pet_dict["id"]
-        cate = petstore_api.Category()
+        cate = Category()
         cate.id = pet_dict["category"]["id"]
         cate.name = pet_dict["category"]["name"]
         pet.category = cate
-        tag1 = petstore_api.Tag()
+        tag1 = Tag()
         tag1.id = pet_dict["tags"][0]["id"]
         tag1.full_name = pet_dict["tags"][0]["fullName"]
-        tag2 = petstore_api.Tag()
+        tag2 = Tag()
         tag2.id = pet_dict["tags"][1]["id"]
         tag2.full_name = pet_dict["tags"][1]["fullName"]
         pet.tags = [tag1, tag2]
@@ -198,7 +202,7 @@ def test_sanitize_for_serialization(self):
 
         # model with additional proerties
         model_dict = {'some_key': True}
-        model = petstore_api.StringBooleanMap(**model_dict)
+        model = StringBooleanMap(**model_dict)
         result = self.api_client.sanitize_for_serialization(model)
         self.assertEqual(result, model_dict)
 
diff --git a/samples/client/petstore/python-experimental/tests/test_api_exception.py b/samples/client/petstore/python-experimental/tests/test_api_exception.py
index b26ef5252bbf..0d0771b57850 100644
--- a/samples/client/petstore/python-experimental/tests/test_api_exception.py
+++ b/samples/client/petstore/python-experimental/tests/test_api_exception.py
@@ -15,7 +15,6 @@
 import unittest
 
 import petstore_api
-from petstore_api.rest import ApiException
 
 from .util import id_gen
 
@@ -23,17 +22,19 @@ class ApiExceptionTests(unittest.TestCase):
 
     def setUp(self):
         self.api_client = petstore_api.ApiClient()
-        self.pet_api = petstore_api.PetApi(self.api_client)
+        from petstore_api.api.pet_api import PetApi
+        self.pet_api = PetApi(self.api_client)
         self.setUpModels()
 
     def setUpModels(self):
-        self.category = petstore_api.Category()
+        from petstore_api.model import category, tag, pet
+        self.category = category.Category()
         self.category.id = id_gen()
         self.category.name = "dog"
-        self.tag = petstore_api.Tag()
+        self.tag = tag.Tag()
         self.tag.id = id_gen()
         self.tag.full_name = "blank"
-        self.pet = petstore_api.Pet(name="hello kity", photo_urls=["http://foo.bar.com/1", "http://foo.bar.com/2"])
+        self.pet = pet.Pet(name="hello kity", photo_urls=["http://foo.bar.com/1", "http://foo.bar.com/2"])
         self.pet.id = id_gen()
         self.pet.status = "sold"
         self.pet.category = self.category
@@ -43,12 +44,12 @@ def test_404_error(self):
         self.pet_api.add_pet(self.pet)
         self.pet_api.delete_pet(pet_id=self.pet.id)
 
-        with self.checkRaiseRegex(ApiException, "Pet not found"):
+        with self.checkRaiseRegex(petstore_api.ApiException, "Pet not found"):
             self.pet_api.get_pet_by_id(pet_id=self.pet.id)
 
         try:
             self.pet_api.get_pet_by_id(pet_id=self.pet.id)
-        except ApiException as e:
+        except petstore_api.ApiException as e:
             self.assertEqual(e.status, 404)
             self.assertEqual(e.reason, "Not Found")
             self.checkRegex(e.body, "Pet not found")
@@ -56,7 +57,7 @@ def test_404_error(self):
     def test_500_error(self):
         self.pet_api.add_pet(self.pet)
 
-        with self.checkRaiseRegex(ApiException, "Internal Server Error"):
+        with self.checkRaiseRegex(petstore_api.ApiException, "Internal Server Error"):
             self.pet_api.upload_file(
                 pet_id=self.pet.id,
                 additional_metadata="special"
@@ -67,7 +68,7 @@ def test_500_error(self):
                 pet_id=self.pet.id,
                 additional_metadata="special"
             )
-        except ApiException as e:
+        except petstore_api.ApiException as e:
             self.assertEqual(e.status, 500)
             self.assertEqual(e.reason, "Internal Server Error")
             self.checkRegex(e.body, "Error 500 Internal Server Error")
diff --git a/samples/client/petstore/python-experimental/tests/test_deserialization.py b/samples/client/petstore/python-experimental/tests/test_deserialization.py
index 83ecabe81d25..f73af24a9425 100644
--- a/samples/client/petstore/python-experimental/tests/test_deserialization.py
+++ b/samples/client/petstore/python-experimental/tests/test_deserialization.py
@@ -24,7 +24,18 @@
     ApiKeyError,
     ApiValueError,
 )
-
+from petstore_api.model import (
+    enum_test,
+    pet,
+    animal,
+    dog,
+    parent_pet,
+    child_lizard,
+    category,
+    outer_enum,
+    outer_number,
+    string_boolean_map,
+)
 from petstore_api.model_utils import (
     file_type,
     int,
@@ -56,19 +67,19 @@ def test_enum_test(self):
         response = MockResponse(data=json.dumps(data))
 
         deserialized = self.deserialize(response,
-            ({str: (petstore_api.EnumTest,)},), True)
+            ({str: (enum_test.EnumTest,)},), True)
         self.assertTrue(isinstance(deserialized, dict))
         self.assertTrue(
-            isinstance(deserialized['enum_test'], petstore_api.EnumTest))
-        outer_enum_value = (
-            petstore_api.OuterEnum.allowed_values[('value',)]["PLACED"])
-        outer_enum = petstore_api.OuterEnum(outer_enum_value)
-        sample_instance = petstore_api.EnumTest(
+            isinstance(deserialized['enum_test'], enum_test.EnumTest))
+        value = (
+            outer_enum.OuterEnum.allowed_values[('value',)]["PLACED"])
+        outer_enum_val = outer_enum.OuterEnum(value)
+        sample_instance = enum_test.EnumTest(
             enum_string="UPPER",
             enum_string_required="lower",
             enum_integer=1,
             enum_number=1.1,
-            outer_enum=outer_enum
+            outer_enum=outer_enum_val
         )
         self.assertEqual(deserialized['enum_test'], sample_instance)
 
@@ -97,9 +108,9 @@ def test_deserialize_dict_str_pet(self):
         response = MockResponse(data=json.dumps(data))
 
         deserialized = self.deserialize(response,
-            ({str: (petstore_api.Pet,)},), True)
+            ({str: (pet.Pet,)},), True)
         self.assertTrue(isinstance(deserialized, dict))
-        self.assertTrue(isinstance(deserialized['pet'], petstore_api.Pet))
+        self.assertTrue(isinstance(deserialized['pet'], pet.Pet))
 
     def test_deserialize_dict_str_dog(self):
         """ deserialize dict(str, Dog), use discriminator"""
@@ -113,13 +124,13 @@ def test_deserialize_dict_str_dog(self):
         response = MockResponse(data=json.dumps(data))
 
         deserialized = self.deserialize(response,
-            ({str: (petstore_api.Animal,)},), True)
+            ({str: (animal.Animal,)},), True)
         self.assertTrue(isinstance(deserialized, dict))
-        dog = deserialized['dog']
-        self.assertTrue(isinstance(dog, petstore_api.Dog))
-        self.assertEqual(dog.class_name, "Dog")
-        self.assertEqual(dog.color, "white")
-        self.assertEqual(dog.breed, "Jack Russel Terrier")
+        dog_inst = deserialized['dog']
+        self.assertTrue(isinstance(dog_inst, dog.Dog))
+        self.assertEqual(dog_inst.class_name, "Dog")
+        self.assertEqual(dog_inst.color, "white")
+        self.assertEqual(dog_inst.breed, "Jack Russel Terrier")
 
     def test_deserialize_lizard(self):
         """ deserialize ChildLizard, use discriminator"""
@@ -130,8 +141,8 @@ def test_deserialize_lizard(self):
         response = MockResponse(data=json.dumps(data))
 
         lizard = self.deserialize(response,
-            (petstore_api.ParentPet,), True)
-        self.assertTrue(isinstance(lizard, petstore_api.ChildLizard))
+            (parent_pet.ParentPet,), True)
+        self.assertTrue(isinstance(lizard, child_lizard.ChildLizard))
         self.assertEqual(lizard.pet_type, "ChildLizard")
         self.assertEqual(lizard.loves_rocks, True)
 
@@ -192,11 +203,11 @@ def test_deserialize_pet(self):
         }
         response = MockResponse(data=json.dumps(data))
 
-        deserialized = self.deserialize(response, (petstore_api.Pet,), True)
-        self.assertTrue(isinstance(deserialized, petstore_api.Pet))
+        deserialized = self.deserialize(response, (pet.Pet,), True)
+        self.assertTrue(isinstance(deserialized, pet.Pet))
         self.assertEqual(deserialized.id, 0)
         self.assertEqual(deserialized.name, "doggie")
-        self.assertTrue(isinstance(deserialized.category, petstore_api.Category))
+        self.assertTrue(isinstance(deserialized.category, category.Category))
         self.assertEqual(deserialized.category.name, "string")
         self.assertTrue(isinstance(deserialized.tags, list))
         self.assertEqual(deserialized.tags[0].full_name, "string")
@@ -243,9 +254,9 @@ def test_deserialize_list_of_pet(self):
         response = MockResponse(data=json.dumps(data))
 
         deserialized = self.deserialize(response,
-            ([petstore_api.Pet],), True)
+            ([pet.Pet],), True)
         self.assertTrue(isinstance(deserialized, list))
-        self.assertTrue(isinstance(deserialized[0], petstore_api.Pet))
+        self.assertTrue(isinstance(deserialized[0], pet.Pet))
         self.assertEqual(deserialized[0].id, 0)
         self.assertEqual(deserialized[1].id, 1)
         self.assertEqual(deserialized[0].name, "doggie0")
@@ -294,19 +305,19 @@ def test_deserialize_OuterEnum(self):
         with self.assertRaises(ApiValueError):
             self.deserialize(
                 MockResponse(data=json.dumps("test str")),
-                (petstore_api.OuterEnum,),
+                (outer_enum.OuterEnum,),
                 True
             )
 
         # valid value works
         placed_str = (
-            petstore_api.OuterEnum.allowed_values[('value',)]["PLACED"]
+            outer_enum.OuterEnum.allowed_values[('value',)]["PLACED"]
         )
         response = MockResponse(data=json.dumps(placed_str))
-        outer_enum = self.deserialize(response,
-            (petstore_api.OuterEnum,), True)
-        self.assertTrue(isinstance(outer_enum, petstore_api.OuterEnum))
-        self.assertTrue(outer_enum.value == placed_str)
+        deserialized = self.deserialize(response,
+            (outer_enum.OuterEnum,), True)
+        self.assertTrue(isinstance(deserialized, outer_enum.OuterEnum))
+        self.assertTrue(deserialized.value == placed_str)
 
     def test_deserialize_OuterNumber(self):
         """ deserialize OuterNumber """
@@ -314,7 +325,7 @@ def test_deserialize_OuterNumber(self):
         with self.assertRaises(ApiTypeError):
             deserialized = self.deserialize(
                 MockResponse(data=json.dumps("test str")),
-                (petstore_api.OuterNumber,),
+                (outer_number.OuterNumber,),
                 True
             )
 
@@ -322,17 +333,17 @@ def test_deserialize_OuterNumber(self):
         with self.assertRaises(ApiValueError):
             deserialized = self.deserialize(
                 MockResponse(data=json.dumps(21.0)),
-                (petstore_api.OuterNumber,),
+                (outer_number.OuterNumber,),
                 True
             )
 
         # valid value works
         number_val = 11.0
         response = MockResponse(data=json.dumps(number_val))
-        outer_number = self.deserialize(response,
-            (petstore_api.OuterNumber,), True)
-        self.assertTrue(isinstance(outer_number, petstore_api.OuterNumber))
-        self.assertTrue(outer_number.value == number_val)
+        number = self.deserialize(response,
+            (outer_number.OuterNumber,), True)
+        self.assertTrue(isinstance(number, outer_number.OuterNumber))
+        self.assertTrue(number.value == number_val)
 
     def test_deserialize_file(self):
         """Ensures that file deserialization works"""
@@ -416,17 +427,17 @@ def test_deserialize_string_boolean_map(self):
         with self.assertRaises(ApiTypeError):
             deserialized = self.deserialize(
                 MockResponse(data=json.dumps("test str")),
-                (petstore_api.StringBooleanMap,),
+                (string_boolean_map.StringBooleanMap,),
                 True
             )
 
         # valid value works
         item_val = {'some_key': True}
         response = MockResponse(data=json.dumps(item_val))
-        model = petstore_api.StringBooleanMap(**item_val)
+        model = string_boolean_map.StringBooleanMap(**item_val)
         deserialized = self.deserialize(response,
-            (petstore_api.StringBooleanMap,), True)
-        self.assertTrue(isinstance(deserialized, petstore_api.StringBooleanMap))
+            (string_boolean_map.StringBooleanMap,), True)
+        self.assertTrue(isinstance(deserialized, string_boolean_map.StringBooleanMap))
         self.assertTrue(deserialized['some_key'] == True)
         self.assertTrue(deserialized == model)
 
diff --git a/samples/client/petstore/python-experimental/tests/test_enum_arrays.py b/samples/client/petstore/python-experimental/tests/test_enum_arrays.py
deleted file mode 100644
index 96edf49c43a9..000000000000
--- a/samples/client/petstore/python-experimental/tests/test_enum_arrays.py
+++ /dev/null
@@ -1,155 +0,0 @@
-# coding: utf-8
-
-# flake8: noqa
-
-"""
-Run the tests.
-$ pip install nose (optional)
-$ cd petstore_api-python
-$ nosetests -v
-"""
-
-import os
-import time
-import unittest
-
-import petstore_api
-
-from petstore_api.exceptions import (
-    ApiTypeError,
-    ApiKeyError,
-    ApiValueError,
-)
-
-class EnumArraysTests(unittest.TestCase):
-
-    def test_enumarrays_init(self):
-      #
-      # Check various combinations of valid values.
-      #
-      fish_or_crab = petstore_api.EnumArrays(just_symbol=">=")
-      self.assertEqual(fish_or_crab.just_symbol, ">=")
-      # if optional property is unset we raise an exception
-      with self.assertRaises(AttributeError) as exc:
-          self.assertEqual(fish_or_crab.array_enum, None)
-
-      fish_or_crab = petstore_api.EnumArrays(just_symbol="$", array_enum=["fish"])
-      self.assertEqual(fish_or_crab.just_symbol, "$")
-      self.assertEqual(fish_or_crab.array_enum, ["fish"])
-
-      fish_or_crab = petstore_api.EnumArrays(just_symbol=">=", array_enum=["fish"])
-      self.assertEqual(fish_or_crab.just_symbol, ">=")
-      self.assertEqual(fish_or_crab.array_enum, ["fish"])
-
-      fish_or_crab = petstore_api.EnumArrays(just_symbol="$", array_enum=["crab"])
-      self.assertEqual(fish_or_crab.just_symbol, "$")
-      self.assertEqual(fish_or_crab.array_enum, ["crab"])
-
-
-      #
-      # Check if setting invalid values fails
-      #
-      with self.assertRaises(ApiValueError) as exc:
-        fish_or_crab = petstore_api.EnumArrays(just_symbol="<=")
-
-      with self.assertRaises(ApiValueError) as exc:
-        fish_or_crab = petstore_api.EnumArrays(just_symbol="$", array_enum=["dog"])
-
-      with self.assertRaises(ApiTypeError) as exc:
-        fish_or_crab = petstore_api.EnumArrays(just_symbol=["$"], array_enum=["crab"])
-
-
-    def test_enumarrays_setter(self):
-
-      #
-      # Check various combinations of valid values
-      #
-      fish_or_crab = petstore_api.EnumArrays()
-
-      fish_or_crab.just_symbol = ">="
-      self.assertEqual(fish_or_crab.just_symbol, ">=")
-
-      fish_or_crab.just_symbol = "$"
-      self.assertEqual(fish_or_crab.just_symbol, "$")
-
-      fish_or_crab.array_enum = []
-      self.assertEqual(fish_or_crab.array_enum, [])
-
-      fish_or_crab.array_enum = ["fish"]
-      self.assertEqual(fish_or_crab.array_enum, ["fish"])
-
-      fish_or_crab.array_enum = ["fish", "fish", "fish"]
-      self.assertEqual(fish_or_crab.array_enum, ["fish", "fish", "fish"])
-
-      fish_or_crab.array_enum = ["crab"]
-      self.assertEqual(fish_or_crab.array_enum, ["crab"])
-
-      fish_or_crab.array_enum = ["crab", "fish"]
-      self.assertEqual(fish_or_crab.array_enum, ["crab", "fish"])
-
-      fish_or_crab.array_enum = ["crab", "fish", "crab", "fish"]
-      self.assertEqual(fish_or_crab.array_enum, ["crab", "fish", "crab", "fish"])
-
-      #
-      # Check if setting invalid values fails
-      #
-      fish_or_crab = petstore_api.EnumArrays()
-      with self.assertRaises(ApiValueError) as exc:
-          fish_or_crab.just_symbol = "!="
-
-      with self.assertRaises(ApiTypeError) as exc:
-        fish_or_crab.just_symbol = ["fish"]
-
-      with self.assertRaises(ApiValueError) as exc:
-        fish_or_crab.array_enum = ["cat"]
-
-      with self.assertRaises(ApiValueError) as exc:
-        fish_or_crab.array_enum = ["fish", "crab", "dog"]
-
-      with self.assertRaises(ApiTypeError) as exc:
-        fish_or_crab.array_enum = "fish"
-
-
-    def test_todict(self):
-      #
-      # Check if dictionary serialization works
-      #
-      dollar_fish_crab_dict = {
-        'just_symbol': "$",
-        'array_enum': ["fish", "crab"]
-      }
-
-      dollar_fish_crab = petstore_api.EnumArrays(
-        just_symbol="$", array_enum=["fish", "crab"])
-
-      self.assertEqual(dollar_fish_crab_dict, dollar_fish_crab.to_dict())
-
-      #
-      # Sanity check for different arrays
-      #
-      dollar_crab_fish_dict = {
-        'just_symbol': "$",
-        'array_enum': ["crab", "fish"]
-      }
-
-      dollar_fish_crab = petstore_api.EnumArrays(
-        just_symbol="$", array_enum=["fish", "crab"])
-
-      self.assertNotEqual(dollar_crab_fish_dict, dollar_fish_crab.to_dict())
-
-
-    def test_equals(self):
-      #
-      # Check if object comparison works
-      #
-      fish1 = petstore_api.EnumArrays(just_symbol="$", array_enum=["fish"])
-      fish2 = petstore_api.EnumArrays(just_symbol="$", array_enum=["fish"])
-      self.assertEqual(fish1, fish2)
-
-      fish = petstore_api.EnumArrays(just_symbol="$", array_enum=["fish"])
-      crab = petstore_api.EnumArrays(just_symbol="$", array_enum=["crab"])
-      self.assertNotEqual(fish, crab)
-
-      dollar = petstore_api.EnumArrays(just_symbol="$")
-      greater = petstore_api.EnumArrays(just_symbol=">=")
-      self.assertNotEqual(dollar, greater)
diff --git a/samples/client/petstore/python-experimental/tests/test_map_test.py b/samples/client/petstore/python-experimental/tests/test_map_test.py
deleted file mode 100644
index 13db5181c9ed..000000000000
--- a/samples/client/petstore/python-experimental/tests/test_map_test.py
+++ /dev/null
@@ -1,117 +0,0 @@
-# coding: utf-8
-
-# flake8: noqa
-
-"""
-Run the tests.
-$ pip install nose (optional)
-$ cd petstore_api-python
-$ nosetests -v
-"""
-
-import os
-import time
-import unittest
-
-import petstore_api
-
-from petstore_api.exceptions import (
-    ApiTypeError,
-    ApiKeyError,
-    ApiValueError,
-)
-
-
-class MapTestTests(unittest.TestCase):
-
-    def test_maptest_init(self):
-      #
-      # Test MapTest construction with valid values
-      #
-      up_or_low_dict = {
-        'UPPER': "UP",
-        'lower': "low"
-      }
-      map_enum_test = petstore_api.MapTest(map_of_enum_string=up_or_low_dict)
-
-      self.assertEqual(map_enum_test.map_of_enum_string, up_or_low_dict)
-
-      map_of_map_of_strings = {
-        'valueDict': up_or_low_dict
-      }
-      map_enum_test = petstore_api.MapTest(map_map_of_string=map_of_map_of_strings)
-
-      self.assertEqual(map_enum_test.map_map_of_string, map_of_map_of_strings)
-
-      #
-      # Make sure that the init fails for invalid enum values
-      #
-      black_or_white_dict = {
-        'black': "UP",
-        'white': "low"
-      }
-      try:
-        map_enum_test = petstore_api.MapTest(map_of_enum_string=black_or_white_dict)
-        self.assertTrue(0)
-      except ValueError:
-        self.assertTrue(1)
-
-    def test_maptest_setter(self):
-      #
-      # Check with some valid values
-      #
-      map_enum_test = petstore_api.MapTest()
-      up_or_low_dict = {
-        'UPPER': "UP",
-        'lower': "low"
-      }
-      map_enum_test.map_of_enum_string = up_or_low_dict
-      self.assertEqual(map_enum_test.map_of_enum_string, up_or_low_dict)
-
-      #
-      # Check if the setter fails for invalid enum values
-      #
-      map_enum_test = petstore_api.MapTest()
-      black_or_white_dict = {
-        'black': "UP",
-        'white': "low"
-      }
-      with self.assertRaises(ApiValueError) as exc:
-        map_enum_test.map_of_enum_string = black_or_white_dict
-
-    def test_todict(self):
-      #
-      # Check dictionary serialization
-      #
-      map_enum_test = petstore_api.MapTest()
-      up_or_low_dict = {
-        'UPPER': "UP",
-        'lower': "low"
-      }
-      map_of_map_of_strings = {
-        'valueDict': up_or_low_dict
-      }
-      indirect_map = petstore_api.StringBooleanMap(**{
-        'option1': True
-      })
-      direct_map = {
-        'option2': False
-      }
-      map_enum_test.map_of_enum_string = up_or_low_dict
-      map_enum_test.map_map_of_string = map_of_map_of_strings
-      map_enum_test.indirect_map = indirect_map
-      map_enum_test.direct_map = direct_map
-
-      self.assertEqual(map_enum_test.map_of_enum_string, up_or_low_dict)
-      self.assertEqual(map_enum_test.map_map_of_string, map_of_map_of_strings)
-      self.assertEqual(map_enum_test.indirect_map, indirect_map)
-      self.assertEqual(map_enum_test.direct_map, direct_map)
-
-      expected_dict = {
-        'map_of_enum_string': up_or_low_dict,
-        'map_map_of_string': map_of_map_of_strings,
-        'indirect_map': indirect_map.to_dict(),
-        'direct_map': direct_map
-      }
-
-      self.assertEqual(map_enum_test.to_dict(), expected_dict)
diff --git a/samples/client/petstore/python-experimental/tests/test_order_model.py b/samples/client/petstore/python-experimental/tests/test_order_model.py
deleted file mode 100644
index 31dc6e3661cd..000000000000
--- a/samples/client/petstore/python-experimental/tests/test_order_model.py
+++ /dev/null
@@ -1,27 +0,0 @@
-# coding: utf-8
-
-# flake8: noqa
-
-"""
-Run the tests.
-$ pip install nose (optional)
-$ cd petstore_api-python
-$ nosetests -v
-"""
-
-import os
-import time
-import unittest
-
-import petstore_api
-
-
-class OrderModelTests(unittest.TestCase):
-
-    def test_status(self):
-        order = petstore_api.Order()
-        order.status = "placed"
-        self.assertEqual("placed", order.status)
-
-        with self.assertRaises(ValueError):
-            order.status = "invalid"
diff --git a/samples/client/petstore/python-experimental/tests/test_pet_api.py b/samples/client/petstore/python-experimental/tests/test_pet_api.py
index ee7e53ecad85..38d7a1cc0b82 100644
--- a/samples/client/petstore/python-experimental/tests/test_pet_api.py
+++ b/samples/client/petstore/python-experimental/tests/test_pet_api.py
@@ -30,7 +30,8 @@
     ApiValueError,
     ApiTypeError,
 )
-
+from petstore_api.api.pet_api import PetApi
+from petstore_api.model import pet
 from .util import id_gen
 
 import urllib3
@@ -75,18 +76,19 @@ def setUp(self):
         config.host = HOST
         config.access_token = 'ACCESS_TOKEN'
         self.api_client = petstore_api.ApiClient(config)
-        self.pet_api = petstore_api.PetApi(self.api_client)
+        self.pet_api = PetApi(self.api_client)
         self.setUpModels()
         self.setUpFiles()
 
     def setUpModels(self):
-        self.category = petstore_api.Category()
+        from petstore_api.model import category, tag
+        self.category = category.Category()
         self.category.id = id_gen()
         self.category.name = "dog"
-        self.tag = petstore_api.Tag()
+        self.tag = tag.Tag()
         self.tag.id = id_gen()
         self.tag.name = "python-pet-tag"
-        self.pet = petstore_api.Pet(name="hello kity", photo_urls=["http://foo.bar.com/1", "http://foo.bar.com/2"])
+        self.pet = pet.Pet(name="hello kity", photo_urls=["http://foo.bar.com/1", "http://foo.bar.com/2"])
         self.pet.id = id_gen()
         self.pet.status = "sold"
         self.pet.category = self.category
@@ -162,8 +164,8 @@ def test_timeout(self):
         self.pet_api.add_pet(self.pet, _request_timeout=(1, 2))
 
     def test_separate_default_client_instances(self):
-        pet_api = petstore_api.PetApi()
-        pet_api2 = petstore_api.PetApi()
+        pet_api = PetApi()
+        pet_api2 = PetApi()
         self.assertNotEqual(pet_api.api_client, pet_api2.api_client)
 
         pet_api.api_client.user_agent = 'api client 3'
@@ -172,8 +174,8 @@ def test_separate_default_client_instances(self):
         self.assertNotEqual(pet_api.api_client.user_agent, pet_api2.api_client.user_agent)
 
     def test_separate_default_config_instances(self):
-        pet_api = petstore_api.PetApi()
-        pet_api2 = petstore_api.PetApi()
+        pet_api = PetApi()
+        pet_api2 = PetApi()
         self.assertNotEqual(pet_api.api_client.configuration, pet_api2.api_client.configuration)
 
         pet_api.api_client.configuration.host = 'somehost'
@@ -187,7 +189,7 @@ def test_async_request(self):
 
         thread = self.pet_api.get_pet_by_id(self.pet.id, async_req=True)
         result = thread.get()
-        self.assertIsInstance(result, petstore_api.Pet)
+        self.assertIsInstance(result, pet.Pet)
 
     def test_async_with_result(self):
         self.pet_api.add_pet(self.pet, async_req=False)
@@ -208,7 +210,7 @@ def test_async_with_http_info(self):
                                             _return_http_data_only=False)
         data, status, headers = thread.get()
 
-        self.assertIsInstance(data, petstore_api.Pet)
+        self.assertIsInstance(data, pet.Pet)
         self.assertEqual(status, 200)
 
     def test_async_exception(self):
diff --git a/samples/client/petstore/python-experimental/tests/test_pet_model.py b/samples/client/petstore/python-experimental/tests/test_pet_model.py
deleted file mode 100644
index c3352015b973..000000000000
--- a/samples/client/petstore/python-experimental/tests/test_pet_model.py
+++ /dev/null
@@ -1,69 +0,0 @@
-# coding: utf-8
-
-# flake8: noqa
-
-"""
-Run the tests.
-$ pip install nose (optional)
-$ cd petstore_api-python
-$ nosetests -v
-"""
-
-import os
-import time
-import unittest
-
-import petstore_api
-
-
-class PetModelTests(unittest.TestCase):
-
-    def setUp(self):
-        self.pet = petstore_api.Pet(name="test name", photo_urls=["string"])
-        self.pet.id = 1
-        self.pet.status = "available"
-        cate = petstore_api.Category()
-        cate.id = 1
-        cate.name = "dog"
-        self.pet.category = cate
-        tag = petstore_api.Tag()
-        tag.id = 1
-        self.pet.tags = [tag]
-
-    def test_to_str(self):
-        data = ("{'category': {'id': 1, 'name': 'dog'},\n"
-                " 'id': 1,\n"
-                " 'name': 'test name',\n"
-                " 'photo_urls': ['string'],\n"
-                " 'status': 'available',\n"
-                " 'tags': [{'id': 1}]}")
-        self.assertEqual(data, self.pet.to_str())
-
-    def test_equal(self):
-        self.pet1 = petstore_api.Pet(name="test name", photo_urls=["string"])
-        self.pet1.id = 1
-        self.pet1.status = "available"
-        cate1 = petstore_api.Category()
-        cate1.id = 1
-        cate1.name = "dog"
-        self.pet.category = cate1
-        tag1 = petstore_api.Tag()
-        tag1.id = 1
-        self.pet1.tags = [tag1]
-
-        self.pet2 = petstore_api.Pet(name="test name", photo_urls=["string"])
-        self.pet2.id = 1
-        self.pet2.status = "available"
-        cate2 = petstore_api.Category()
-        cate2.id = 1
-        cate2.name = "dog"
-        self.pet.category = cate2
-        tag2 = petstore_api.Tag()
-        tag2.id = 1
-        self.pet2.tags = [tag2]
-
-        self.assertTrue(self.pet1 == self.pet2)
-
-        # reset pet1 tags to empty array so that object comparison returns false
-        self.pet1.tags = []
-        self.assertFalse(self.pet1 == self.pet2)
diff --git a/samples/client/petstore/python-experimental/tests/test_store_api.py b/samples/client/petstore/python-experimental/tests/test_store_api.py
index 1817477aba69..a7c1d5dd6670 100644
--- a/samples/client/petstore/python-experimental/tests/test_store_api.py
+++ b/samples/client/petstore/python-experimental/tests/test_store_api.py
@@ -14,13 +14,13 @@
 import unittest
 
 import petstore_api
-from petstore_api.rest import ApiException
+from petstore_api.api.store_api import StoreApi
 
 
 class StoreApiTests(unittest.TestCase):
 
     def setUp(self):
-        self.store_api = petstore_api.StoreApi()
+        self.store_api = StoreApi()
 
     def tearDown(self):
         # sleep 1 sec between two every 2 tests
diff --git a/samples/openapi3/client/petstore/python-experimental/.openapi-generator/FILES b/samples/openapi3/client/petstore/python-experimental/.openapi-generator/FILES
index 378e6965acc8..ffc326a12f08 100644
--- a/samples/openapi3/client/petstore/python-experimental/.openapi-generator/FILES
+++ b/samples/openapi3/client/petstore/python-experimental/.openapi-generator/FILES
@@ -102,92 +102,94 @@ petstore_api/api/pet_api.py
 petstore_api/api/store_api.py
 petstore_api/api/user_api.py
 petstore_api/api_client.py
+petstore_api/apis/__init__.py
 petstore_api/configuration.py
 petstore_api/exceptions.py
+petstore_api/model/__init__.py
+petstore_api/model/additional_properties_class.py
+petstore_api/model/address.py
+petstore_api/model/animal.py
+petstore_api/model/api_response.py
+petstore_api/model/apple.py
+petstore_api/model/apple_req.py
+petstore_api/model/array_of_array_of_number_only.py
+petstore_api/model/array_of_number_only.py
+petstore_api/model/array_test.py
+petstore_api/model/banana.py
+petstore_api/model/banana_req.py
+petstore_api/model/basque_pig.py
+petstore_api/model/capitalization.py
+petstore_api/model/cat.py
+petstore_api/model/cat_all_of.py
+petstore_api/model/category.py
+petstore_api/model/child_cat.py
+petstore_api/model/child_cat_all_of.py
+petstore_api/model/class_model.py
+petstore_api/model/client.py
+petstore_api/model/complex_quadrilateral.py
+petstore_api/model/danish_pig.py
+petstore_api/model/dog.py
+petstore_api/model/dog_all_of.py
+petstore_api/model/drawing.py
+petstore_api/model/enum_arrays.py
+petstore_api/model/enum_class.py
+petstore_api/model/enum_test.py
+petstore_api/model/equilateral_triangle.py
+petstore_api/model/file.py
+petstore_api/model/file_schema_test_class.py
+petstore_api/model/foo.py
+petstore_api/model/format_test.py
+petstore_api/model/fruit.py
+petstore_api/model/fruit_req.py
+petstore_api/model/gm_fruit.py
+petstore_api/model/grandparent_animal.py
+petstore_api/model/has_only_read_only.py
+petstore_api/model/health_check_result.py
+petstore_api/model/inline_object.py
+petstore_api/model/inline_object1.py
+petstore_api/model/inline_object2.py
+petstore_api/model/inline_object3.py
+petstore_api/model/inline_object4.py
+petstore_api/model/inline_object5.py
+petstore_api/model/inline_response_default.py
+petstore_api/model/isosceles_triangle.py
+petstore_api/model/list.py
+petstore_api/model/mammal.py
+petstore_api/model/map_test.py
+petstore_api/model/mixed_properties_and_additional_properties_class.py
+petstore_api/model/model200_response.py
+petstore_api/model/model_return.py
+petstore_api/model/name.py
+petstore_api/model/nullable_class.py
+petstore_api/model/nullable_shape.py
+petstore_api/model/number_only.py
+petstore_api/model/order.py
+petstore_api/model/outer_composite.py
+petstore_api/model/outer_enum.py
+petstore_api/model/outer_enum_default_value.py
+petstore_api/model/outer_enum_integer.py
+petstore_api/model/outer_enum_integer_default_value.py
+petstore_api/model/parent_pet.py
+petstore_api/model/pet.py
+petstore_api/model/pig.py
+petstore_api/model/quadrilateral.py
+petstore_api/model/quadrilateral_interface.py
+petstore_api/model/read_only_first.py
+petstore_api/model/scalene_triangle.py
+petstore_api/model/shape.py
+petstore_api/model/shape_interface.py
+petstore_api/model/shape_or_null.py
+petstore_api/model/simple_quadrilateral.py
+petstore_api/model/special_model_name.py
+petstore_api/model/string_boolean_map.py
+petstore_api/model/tag.py
+petstore_api/model/triangle.py
+petstore_api/model/triangle_interface.py
+petstore_api/model/user.py
+petstore_api/model/whale.py
+petstore_api/model/zebra.py
 petstore_api/model_utils.py
 petstore_api/models/__init__.py
-petstore_api/models/additional_properties_class.py
-petstore_api/models/address.py
-petstore_api/models/animal.py
-petstore_api/models/api_response.py
-petstore_api/models/apple.py
-petstore_api/models/apple_req.py
-petstore_api/models/array_of_array_of_number_only.py
-petstore_api/models/array_of_number_only.py
-petstore_api/models/array_test.py
-petstore_api/models/banana.py
-petstore_api/models/banana_req.py
-petstore_api/models/basque_pig.py
-petstore_api/models/capitalization.py
-petstore_api/models/cat.py
-petstore_api/models/cat_all_of.py
-petstore_api/models/category.py
-petstore_api/models/child_cat.py
-petstore_api/models/child_cat_all_of.py
-petstore_api/models/class_model.py
-petstore_api/models/client.py
-petstore_api/models/complex_quadrilateral.py
-petstore_api/models/danish_pig.py
-petstore_api/models/dog.py
-petstore_api/models/dog_all_of.py
-petstore_api/models/drawing.py
-petstore_api/models/enum_arrays.py
-petstore_api/models/enum_class.py
-petstore_api/models/enum_test.py
-petstore_api/models/equilateral_triangle.py
-petstore_api/models/file.py
-petstore_api/models/file_schema_test_class.py
-petstore_api/models/foo.py
-petstore_api/models/format_test.py
-petstore_api/models/fruit.py
-petstore_api/models/fruit_req.py
-petstore_api/models/gm_fruit.py
-petstore_api/models/grandparent_animal.py
-petstore_api/models/has_only_read_only.py
-petstore_api/models/health_check_result.py
-petstore_api/models/inline_object.py
-petstore_api/models/inline_object1.py
-petstore_api/models/inline_object2.py
-petstore_api/models/inline_object3.py
-petstore_api/models/inline_object4.py
-petstore_api/models/inline_object5.py
-petstore_api/models/inline_response_default.py
-petstore_api/models/isosceles_triangle.py
-petstore_api/models/list.py
-petstore_api/models/mammal.py
-petstore_api/models/map_test.py
-petstore_api/models/mixed_properties_and_additional_properties_class.py
-petstore_api/models/model200_response.py
-petstore_api/models/model_return.py
-petstore_api/models/name.py
-petstore_api/models/nullable_class.py
-petstore_api/models/nullable_shape.py
-petstore_api/models/number_only.py
-petstore_api/models/order.py
-petstore_api/models/outer_composite.py
-petstore_api/models/outer_enum.py
-petstore_api/models/outer_enum_default_value.py
-petstore_api/models/outer_enum_integer.py
-petstore_api/models/outer_enum_integer_default_value.py
-petstore_api/models/parent_pet.py
-petstore_api/models/pet.py
-petstore_api/models/pig.py
-petstore_api/models/quadrilateral.py
-petstore_api/models/quadrilateral_interface.py
-petstore_api/models/read_only_first.py
-petstore_api/models/scalene_triangle.py
-petstore_api/models/shape.py
-petstore_api/models/shape_interface.py
-petstore_api/models/shape_or_null.py
-petstore_api/models/simple_quadrilateral.py
-petstore_api/models/special_model_name.py
-petstore_api/models/string_boolean_map.py
-petstore_api/models/tag.py
-petstore_api/models/triangle.py
-petstore_api/models/triangle_interface.py
-petstore_api/models/user.py
-petstore_api/models/whale.py
-petstore_api/models/zebra.py
 petstore_api/rest.py
 petstore_api/signing.py
 requirements.txt
diff --git a/samples/openapi3/client/petstore/python-experimental/README.md b/samples/openapi3/client/petstore/python-experimental/README.md
index 9827e98d2a13..a542d727b93d 100644
--- a/samples/openapi3/client/petstore/python-experimental/README.md
+++ b/samples/openapi3/client/petstore/python-experimental/README.md
@@ -50,7 +50,8 @@ import datetime
 import time
 import petstore_api
 from pprint import pprint
-
+from petstore_api.api import another_fake_api
+from petstore_api.model import client
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
 configuration = petstore_api.Configuration(
@@ -62,8 +63,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.AnotherFakeApi(api_client)
-    client_client = petstore_api.Client() # client.Client | client model
+    api_instance = another_fake_api.AnotherFakeApi(api_client)
+    client_client = client.Client() # client.Client | client model
 
     try:
         # To test special tags
@@ -71,7 +72,6 @@ with petstore_api.ApiClient(configuration) as api_client:
         pprint(api_response)
     except petstore_api.ApiException as e:
         print("Exception when calling AnotherFakeApi->call_123_test_special_tags: %s\n" % e)
-    
 ```
 
 ## Documentation for API Endpoints
@@ -253,3 +253,22 @@ Class | Method | HTTP request | Description
 
 
 
+## Notes for Large OpenAPI documents
+If the OpenAPI document is large, imports in petstore_api.apis and petstore_api.models may fail with a
+RecursionError indicating the maximum recursion limit has been exceeded. In that case, there are a couple of solutions:
+
+Solution 1:
+Use specific imports for apis and models like:
+- `from petstore_api.api.default_api import DefaultApi`
+- `from petstore_api.model.pet import Pet`
+
+Solution 1:
+Before importing the package, adjust the maximum recursion limit as shown below:
+```
+import sys
+sys.setrecursionlimit(1500)
+import petstore_api
+from petstore_api.apis import *
+from petstore_api.models import *
+```
+
diff --git a/samples/openapi3/client/petstore/python-experimental/docs/AnotherFakeApi.md b/samples/openapi3/client/petstore/python-experimental/docs/AnotherFakeApi.md
index 7b8b3d6796d0..4290afb9ab04 100644
--- a/samples/openapi3/client/petstore/python-experimental/docs/AnotherFakeApi.md
+++ b/samples/openapi3/client/petstore/python-experimental/docs/AnotherFakeApi.md
@@ -20,6 +20,8 @@ To test special tags and operation ID starting with number
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import another_fake_api
+from petstore_api.model import client
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -31,8 +33,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.AnotherFakeApi(api_client)
-    client_client = petstore_api.Client() # client.Client | client model
+    api_instance = another_fake_api.AnotherFakeApi(api_client)
+    client_client = client.Client() # client.Client | client model
     
     # example passing only required values which don't have defaults set
     try:
diff --git a/samples/openapi3/client/petstore/python-experimental/docs/DefaultApi.md b/samples/openapi3/client/petstore/python-experimental/docs/DefaultApi.md
index 91623f7a45ae..d5e28c8bc429 100644
--- a/samples/openapi3/client/petstore/python-experimental/docs/DefaultApi.md
+++ b/samples/openapi3/client/petstore/python-experimental/docs/DefaultApi.md
@@ -18,6 +18,8 @@ Method | HTTP request | Description
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import default_api
+from petstore_api.model import inline_response_default
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -29,7 +31,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.DefaultApi(api_client)
+    api_instance = default_api.DefaultApi(api_client)
     
     # example, this endpoint has no required or optional parameters
     try:
diff --git a/samples/openapi3/client/petstore/python-experimental/docs/FakeApi.md b/samples/openapi3/client/petstore/python-experimental/docs/FakeApi.md
index a31649db9aaf..6bd8936f1b5b 100644
--- a/samples/openapi3/client/petstore/python-experimental/docs/FakeApi.md
+++ b/samples/openapi3/client/petstore/python-experimental/docs/FakeApi.md
@@ -31,6 +31,8 @@ Health check endpoint
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
+from petstore_api.model import health_check_result
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -42,7 +44,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     
     # example, this endpoint has no required or optional parameters
     try:
@@ -89,6 +91,7 @@ Test serialization of outer boolean types
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -100,7 +103,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     body = True # bool | Input boolean as post body (optional)
 
     # example passing only required values which don't have defaults set
@@ -151,6 +154,8 @@ Test serialization of object with outer number type
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
+from petstore_api.model import outer_composite
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -162,8 +167,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
-    outer_composite_outer_composite = petstore_api.OuterComposite() # outer_composite.OuterComposite | Input composite as post body (optional)
+    api_instance = fake_api.FakeApi(api_client)
+    outer_composite_outer_composite = outer_composite.OuterComposite() # outer_composite.OuterComposite | Input composite as post body (optional)
 
     # example passing only required values which don't have defaults set
     # and optional values
@@ -213,6 +218,7 @@ Test serialization of outer number types
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -224,7 +230,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     body = 3.4 # float | Input number as post body (optional)
 
     # example passing only required values which don't have defaults set
@@ -275,6 +281,7 @@ Test serialization of outer string types
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -286,7 +293,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     body = 'body_example' # str | Input string as post body (optional)
 
     # example passing only required values which don't have defaults set
@@ -337,6 +344,8 @@ For this test, the body for this request much reference a schema named `File`.
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
+from petstore_api.model import file_schema_test_class
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -348,8 +357,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
-    file_schema_test_class_file_schema_test_class = petstore_api.FileSchemaTestClass() # file_schema_test_class.FileSchemaTestClass | 
+    api_instance = fake_api.FakeApi(api_client)
+    file_schema_test_class_file_schema_test_class = file_schema_test_class.FileSchemaTestClass() # file_schema_test_class.FileSchemaTestClass | 
     
     # example passing only required values which don't have defaults set
     try:
@@ -395,6 +404,8 @@ No authorization required
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
+from petstore_api.model import user
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -406,9 +417,9 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     query = 'query_example' # str | 
-    user_user = petstore_api.User() # user.User | 
+    user_user = user.User() # user.User | 
     
     # example passing only required values which don't have defaults set
     try:
@@ -457,6 +468,8 @@ To test \"client\" model
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
+from petstore_api.model import client
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -468,8 +481,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
-    client_client = petstore_api.Client() # client.Client | client model
+    api_instance = fake_api.FakeApi(api_client)
+    client_client = client.Client() # client.Client | client model
     
     # example passing only required values which don't have defaults set
     try:
@@ -520,6 +533,7 @@ Fake endpoint for testing various parameters 假端點 偽のエンドポイン
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -541,7 +555,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     number = 3.4 # float | None
     double = 3.4 # float | None
     pattern_without_delimiter = 'pattern_without_delimiter_example' # str | None
@@ -626,6 +640,7 @@ To test enum parameters
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -637,7 +652,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     enum_header_string_array = ['enum_header_string_array_example'] # [str] | Header parameter enum test (string array) (optional)
 enum_header_string = '-efg' # str | Header parameter enum test (string) (optional) if omitted the server will use the default value of '-efg'
 enum_query_string_array = ['enum_query_string_array_example'] # [str] | Query parameter enum test (string array) (optional)
@@ -704,6 +719,7 @@ Fake endpoint to test group parameters (optional)
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -724,7 +740,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     required_string_group = 56 # int | Required String in group parameters
     required_boolean_group = True # bool | Required Boolean in group parameters
     required_int64_group = 56 # int | Required Integer in group parameters
@@ -790,6 +806,7 @@ test inline additionalProperties
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -801,7 +818,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     request_body = {'key': 'request_body_example'} # {str: (str,)} | request body
     
     # example passing only required values which don't have defaults set
@@ -849,6 +866,7 @@ test json serialization of form data
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -860,7 +878,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     param = 'param_example' # str | field1
     param2 = 'param2_example' # str | field2
     
@@ -912,6 +930,7 @@ To test the collection format in query parameters
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -923,7 +942,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeApi(api_client)
+    api_instance = fake_api.FakeApi(api_client)
     pipe = ['pipe_example'] # [str] | 
     ioutil = ['ioutil_example'] # [str] | 
     http = ['http_example'] # [str] | 
diff --git a/samples/openapi3/client/petstore/python-experimental/docs/FakeClassnameTags123Api.md b/samples/openapi3/client/petstore/python-experimental/docs/FakeClassnameTags123Api.md
index ab1eb4d62ca8..3568b3be2399 100644
--- a/samples/openapi3/client/petstore/python-experimental/docs/FakeClassnameTags123Api.md
+++ b/samples/openapi3/client/petstore/python-experimental/docs/FakeClassnameTags123Api.md
@@ -21,6 +21,8 @@ To test class name in snake case
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import fake_classname_tags_123_api
+from petstore_api.model import client
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -46,8 +48,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.FakeClassnameTags123Api(api_client)
-    client_client = petstore_api.Client() # client.Client | client model
+    api_instance = fake_classname_tags_123_api.FakeClassnameTags123Api(api_client)
+    client_client = client.Client() # client.Client | client model
     
     # example passing only required values which don't have defaults set
     try:
diff --git a/samples/openapi3/client/petstore/python-experimental/docs/PetApi.md b/samples/openapi3/client/petstore/python-experimental/docs/PetApi.md
index 62bcfdd1bdd1..a5344a30f168 100644
--- a/samples/openapi3/client/petstore/python-experimental/docs/PetApi.md
+++ b/samples/openapi3/client/petstore/python-experimental/docs/PetApi.md
@@ -27,6 +27,8 @@ Add a new pet to the store
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
+from petstore_api.model import pet
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -108,8 +110,8 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
-    pet_pet = petstore_api.Pet() # pet.Pet | Pet object that needs to be added to the store
+    api_instance = pet_api.PetApi(api_client)
+    pet_pet = pet.Pet() # pet.Pet | Pet object that needs to be added to the store
     
     # example passing only required values which don't have defaults set
     try:
@@ -157,6 +159,7 @@ Deletes a pet
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -178,7 +181,7 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
+    api_instance = pet_api.PetApi(api_client)
     pet_id = 56 # int | Pet id to delete
     api_key = 'api_key_example' # str |  (optional)
 
@@ -239,6 +242,8 @@ Multiple status values can be provided with comma separated strings
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
+from petstore_api.model import pet
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -320,7 +325,7 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
+    api_instance = pet_api.PetApi(api_client)
     status = ['status_example'] # [str] | Status values that need to be considered for filter
     
     # example passing only required values which don't have defaults set
@@ -373,6 +378,8 @@ Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
+from petstore_api.model import pet
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -454,7 +461,7 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
+    api_instance = pet_api.PetApi(api_client)
     tags = ['tags_example'] # [str] | Tags to filter by
     
     # example passing only required values which don't have defaults set
@@ -507,6 +514,8 @@ Returns a single pet
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
+from petstore_api.model import pet
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -532,7 +541,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
+    api_instance = pet_api.PetApi(api_client)
     pet_id = 56 # int | ID of pet to return
     
     # example passing only required values which don't have defaults set
@@ -584,6 +593,8 @@ Update an existing pet
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
+from petstore_api.model import pet
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -665,8 +676,8 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
-    pet_pet = petstore_api.Pet() # pet.Pet | Pet object that needs to be added to the store
+    api_instance = pet_api.PetApi(api_client)
+    pet_pet = pet.Pet() # pet.Pet | Pet object that needs to be added to the store
     
     # example passing only required values which don't have defaults set
     try:
@@ -716,6 +727,7 @@ Updates a pet in the store with form data
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -737,7 +749,7 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
+    api_instance = pet_api.PetApi(api_client)
     pet_id = 56 # int | ID of pet that needs to be updated
     name = 'name_example' # str | Updated name of the pet (optional)
 status = 'status_example' # str | Updated status of the pet (optional)
@@ -798,6 +810,8 @@ uploads an image
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
+from petstore_api.model import api_response
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -819,7 +833,7 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
+    api_instance = pet_api.PetApi(api_client)
     pet_id = 56 # int | ID of pet to update
     additional_metadata = 'additional_metadata_example' # str | Additional data to pass to server (optional)
 file = open('/path/to/file', 'rb') # file_type | file to upload (optional)
@@ -882,6 +896,8 @@ uploads an image (required)
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import pet_api
+from petstore_api.model import api_response
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -903,7 +919,7 @@ configuration.access_token = 'YOUR_ACCESS_TOKEN'
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.PetApi(api_client)
+    api_instance = pet_api.PetApi(api_client)
     pet_id = 56 # int | ID of pet to update
     required_file = open('/path/to/file', 'rb') # file_type | file to upload
     additional_metadata = 'additional_metadata_example' # str | Additional data to pass to server (optional)
diff --git a/samples/openapi3/client/petstore/python-experimental/docs/StoreApi.md b/samples/openapi3/client/petstore/python-experimental/docs/StoreApi.md
index 4a7b890a1cc1..2cebd103e1f8 100644
--- a/samples/openapi3/client/petstore/python-experimental/docs/StoreApi.md
+++ b/samples/openapi3/client/petstore/python-experimental/docs/StoreApi.md
@@ -23,6 +23,7 @@ For valid response try integer IDs with value < 1000. Anything above 1000 or non
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import store_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -34,7 +35,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.StoreApi(api_client)
+    api_instance = store_api.StoreApi(api_client)
     order_id = 'order_id_example' # str | ID of the order that needs to be deleted
     
     # example passing only required values which don't have defaults set
@@ -86,6 +87,7 @@ Returns a map of status codes to quantities
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import store_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -111,7 +113,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.StoreApi(api_client)
+    api_instance = store_api.StoreApi(api_client)
     
     # example, this endpoint has no required or optional parameters
     try:
@@ -158,6 +160,8 @@ For valid response try integer IDs with value <= 5 or > 10. Other values will ge
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import store_api
+from petstore_api.model import order
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -169,7 +173,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.StoreApi(api_client)
+    api_instance = store_api.StoreApi(api_client)
     order_id = 56 # int | ID of pet that needs to be fetched
     
     # example passing only required values which don't have defaults set
@@ -220,6 +224,8 @@ Place an order for a pet
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import store_api
+from petstore_api.model import order
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -231,8 +237,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.StoreApi(api_client)
-    order_order = petstore_api.Order() # order.Order | order placed for purchasing the pet
+    api_instance = store_api.StoreApi(api_client)
+    order_order = order.Order() # order.Order | order placed for purchasing the pet
     
     # example passing only required values which don't have defaults set
     try:
diff --git a/samples/openapi3/client/petstore/python-experimental/docs/UserApi.md b/samples/openapi3/client/petstore/python-experimental/docs/UserApi.md
index 4aa31e100bb0..ffcdef6d343c 100644
--- a/samples/openapi3/client/petstore/python-experimental/docs/UserApi.md
+++ b/samples/openapi3/client/petstore/python-experimental/docs/UserApi.md
@@ -27,6 +27,8 @@ This can only be done by the logged in user.
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
+from petstore_api.model import user
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -38,8 +40,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
-    user_user = petstore_api.User() # user.User | Created user object
+    api_instance = user_api.UserApi(api_client)
+    user_user = user.User() # user.User | Created user object
     
     # example passing only required values which don't have defaults set
     try:
@@ -86,6 +88,8 @@ Creates list of users with given input array
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
+from petstore_api.model import user
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -97,8 +101,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
-    user_user = [petstore_api.User()] # [user.User] | List of user object
+    api_instance = user_api.UserApi(api_client)
+    user_user = [user.User()] # [user.User] | List of user object
     
     # example passing only required values which don't have defaults set
     try:
@@ -145,6 +149,8 @@ Creates list of users with given input array
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
+from petstore_api.model import user
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -156,8 +162,8 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
-    user_user = [petstore_api.User()] # [user.User] | List of user object
+    api_instance = user_api.UserApi(api_client)
+    user_user = [user.User()] # [user.User] | List of user object
     
     # example passing only required values which don't have defaults set
     try:
@@ -206,6 +212,7 @@ This can only be done by the logged in user.
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -217,7 +224,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
+    api_instance = user_api.UserApi(api_client)
     username = 'username_example' # str | The name that needs to be deleted
     
     # example passing only required values which don't have defaults set
@@ -266,6 +273,8 @@ Get user by user name
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
+from petstore_api.model import user
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -277,7 +286,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
+    api_instance = user_api.UserApi(api_client)
     username = 'username_example' # str | The name that needs to be fetched. Use user1 for testing.
     
     # example passing only required values which don't have defaults set
@@ -328,6 +337,7 @@ Logs user into the system
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -339,7 +349,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
+    api_instance = user_api.UserApi(api_client)
     username = 'username_example' # str | The user name for login
     password = 'password_example' # str | The password for login in clear text
     
@@ -391,6 +401,7 @@ Logs out current logged in user session
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -402,7 +413,7 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
+    api_instance = user_api.UserApi(api_client)
     
     # example, this endpoint has no required or optional parameters
     try:
@@ -448,6 +459,8 @@ This can only be done by the logged in user.
 from __future__ import print_function
 import time
 import petstore_api
+from petstore_api.api import user_api
+from petstore_api.model import user
 from pprint import pprint
 # Defining the host is optional and defaults to http://petstore.swagger.io:80/v2
 # See configuration.py for a list of all supported configuration parameters.
@@ -459,9 +472,9 @@ configuration = petstore_api.Configuration(
 # Enter a context with an instance of the API client
 with petstore_api.ApiClient() as api_client:
     # Create an instance of the API class
-    api_instance = petstore_api.UserApi(api_client)
+    api_instance = user_api.UserApi(api_client)
     username = 'username_example' # str | name that need to be deleted
-    user_user = petstore_api.User() # user.User | Updated user object
+    user_user = user.User() # user.User | Updated user object
     
     # example passing only required values which don't have defaults set
     try:
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/__init__.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/__init__.py
index 8b945d032fbe..fb7630e30d59 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/__init__.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/__init__.py
@@ -16,15 +16,6 @@
 
 __version__ = "1.0.0"
 
-# import apis into sdk package
-from petstore_api.api.another_fake_api import AnotherFakeApi
-from petstore_api.api.default_api import DefaultApi
-from petstore_api.api.fake_api import FakeApi
-from petstore_api.api.fake_classname_tags_123_api import FakeClassnameTags123Api
-from petstore_api.api.pet_api import PetApi
-from petstore_api.api.store_api import StoreApi
-from petstore_api.api.user_api import UserApi
-
 # import ApiClient
 from petstore_api.api_client import ApiClient
 
@@ -34,91 +25,8 @@
 
 # import exceptions
 from petstore_api.exceptions import OpenApiException
+from petstore_api.exceptions import ApiAttributeError
 from petstore_api.exceptions import ApiTypeError
 from petstore_api.exceptions import ApiValueError
 from petstore_api.exceptions import ApiKeyError
-from petstore_api.exceptions import ApiException
-
-# import models into sdk package
-from petstore_api.models.additional_properties_class import AdditionalPropertiesClass
-from petstore_api.models.address import Address
-from petstore_api.models.animal import Animal
-from petstore_api.models.api_response import ApiResponse
-from petstore_api.models.apple import Apple
-from petstore_api.models.apple_req import AppleReq
-from petstore_api.models.array_of_array_of_number_only import ArrayOfArrayOfNumberOnly
-from petstore_api.models.array_of_number_only import ArrayOfNumberOnly
-from petstore_api.models.array_test import ArrayTest
-from petstore_api.models.banana import Banana
-from petstore_api.models.banana_req import BananaReq
-from petstore_api.models.basque_pig import BasquePig
-from petstore_api.models.capitalization import Capitalization
-from petstore_api.models.cat import Cat
-from petstore_api.models.cat_all_of import CatAllOf
-from petstore_api.models.category import Category
-from petstore_api.models.child_cat import ChildCat
-from petstore_api.models.child_cat_all_of import ChildCatAllOf
-from petstore_api.models.class_model import ClassModel
-from petstore_api.models.client import Client
-from petstore_api.models.complex_quadrilateral import ComplexQuadrilateral
-from petstore_api.models.danish_pig import DanishPig
-from petstore_api.models.dog import Dog
-from petstore_api.models.dog_all_of import DogAllOf
-from petstore_api.models.drawing import Drawing
-from petstore_api.models.enum_arrays import EnumArrays
-from petstore_api.models.enum_class import EnumClass
-from petstore_api.models.enum_test import EnumTest
-from petstore_api.models.equilateral_triangle import EquilateralTriangle
-from petstore_api.models.file import File
-from petstore_api.models.file_schema_test_class import FileSchemaTestClass
-from petstore_api.models.foo import Foo
-from petstore_api.models.format_test import FormatTest
-from petstore_api.models.fruit import Fruit
-from petstore_api.models.fruit_req import FruitReq
-from petstore_api.models.gm_fruit import GmFruit
-from petstore_api.models.grandparent_animal import GrandparentAnimal
-from petstore_api.models.has_only_read_only import HasOnlyReadOnly
-from petstore_api.models.health_check_result import HealthCheckResult
-from petstore_api.models.inline_object import InlineObject
-from petstore_api.models.inline_object1 import InlineObject1
-from petstore_api.models.inline_object2 import InlineObject2
-from petstore_api.models.inline_object3 import InlineObject3
-from petstore_api.models.inline_object4 import InlineObject4
-from petstore_api.models.inline_object5 import InlineObject5
-from petstore_api.models.inline_response_default import InlineResponseDefault
-from petstore_api.models.isosceles_triangle import IsoscelesTriangle
-from petstore_api.models.list import List
-from petstore_api.models.mammal import Mammal
-from petstore_api.models.map_test import MapTest
-from petstore_api.models.mixed_properties_and_additional_properties_class import MixedPropertiesAndAdditionalPropertiesClass
-from petstore_api.models.model200_response import Model200Response
-from petstore_api.models.model_return import ModelReturn
-from petstore_api.models.name import Name
-from petstore_api.models.nullable_class import NullableClass
-from petstore_api.models.nullable_shape import NullableShape
-from petstore_api.models.number_only import NumberOnly
-from petstore_api.models.order import Order
-from petstore_api.models.outer_composite import OuterComposite
-from petstore_api.models.outer_enum import OuterEnum
-from petstore_api.models.outer_enum_default_value import OuterEnumDefaultValue
-from petstore_api.models.outer_enum_integer import OuterEnumInteger
-from petstore_api.models.outer_enum_integer_default_value import OuterEnumIntegerDefaultValue
-from petstore_api.models.parent_pet import ParentPet
-from petstore_api.models.pet import Pet
-from petstore_api.models.pig import Pig
-from petstore_api.models.quadrilateral import Quadrilateral
-from petstore_api.models.quadrilateral_interface import QuadrilateralInterface
-from petstore_api.models.read_only_first import ReadOnlyFirst
-from petstore_api.models.scalene_triangle import ScaleneTriangle
-from petstore_api.models.shape import Shape
-from petstore_api.models.shape_interface import ShapeInterface
-from petstore_api.models.shape_or_null import ShapeOrNull
-from petstore_api.models.simple_quadrilateral import SimpleQuadrilateral
-from petstore_api.models.special_model_name import SpecialModelName
-from petstore_api.models.string_boolean_map import StringBooleanMap
-from petstore_api.models.tag import Tag
-from petstore_api.models.triangle import Triangle
-from petstore_api.models.triangle_interface import TriangleInterface
-from petstore_api.models.user import User
-from petstore_api.models.whale import Whale
-from petstore_api.models.zebra import Zebra
+from petstore_api.exceptions import ApiException
\ No newline at end of file
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/api/another_fake_api.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/api/another_fake_api.py
index 6c7e40c24825..cb2881b7ae8c 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/api/another_fake_api.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/api/another_fake_api.py
@@ -34,7 +34,7 @@
     str,
     validate_and_convert_types
 )
-from petstore_api.models import client
+from petstore_api.model import client
 
 
 class AnotherFakeApi(object):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/api/default_api.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/api/default_api.py
index 3e46d7928cb5..25c8e40e5252 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/api/default_api.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/api/default_api.py
@@ -34,7 +34,7 @@
     str,
     validate_and_convert_types
 )
-from petstore_api.models import inline_response_default
+from petstore_api.model import inline_response_default
 
 
 class DefaultApi(object):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/api/fake_api.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/api/fake_api.py
index fd5096ba6de1..69531b0525fa 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/api/fake_api.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/api/fake_api.py
@@ -34,11 +34,11 @@
     str,
     validate_and_convert_types
 )
-from petstore_api.models import health_check_result
-from petstore_api.models import outer_composite
-from petstore_api.models import file_schema_test_class
-from petstore_api.models import user
-from petstore_api.models import client
+from petstore_api.model import health_check_result
+from petstore_api.model import outer_composite
+from petstore_api.model import file_schema_test_class
+from petstore_api.model import user
+from petstore_api.model import client
 
 
 class FakeApi(object):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/api/fake_classname_tags_123_api.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/api/fake_classname_tags_123_api.py
index f2a13a0b92fd..2ed92b4d0f33 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/api/fake_classname_tags_123_api.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/api/fake_classname_tags_123_api.py
@@ -34,7 +34,7 @@
     str,
     validate_and_convert_types
 )
-from petstore_api.models import client
+from petstore_api.model import client
 
 
 class FakeClassnameTags123Api(object):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/api/pet_api.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/api/pet_api.py
index 1a0fdb48bf4c..9ccaf11c268d 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/api/pet_api.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/api/pet_api.py
@@ -34,8 +34,8 @@
     str,
     validate_and_convert_types
 )
-from petstore_api.models import pet
-from petstore_api.models import api_response
+from petstore_api.model import pet
+from petstore_api.model import api_response
 
 
 class PetApi(object):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/api/store_api.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/api/store_api.py
index 46fce50d29d3..67648f5ee722 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/api/store_api.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/api/store_api.py
@@ -34,7 +34,7 @@
     str,
     validate_and_convert_types
 )
-from petstore_api.models import order
+from petstore_api.model import order
 
 
 class StoreApi(object):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/api/user_api.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/api/user_api.py
index e354babbfe5c..e5f5ffe886c9 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/api/user_api.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/api/user_api.py
@@ -34,7 +34,7 @@
     str,
     validate_and_convert_types
 )
-from petstore_api.models import user
+from petstore_api.model import user
 
 
 class UserApi(object):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/apis/__init__.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/apis/__init__.py
new file mode 100644
index 000000000000..41cbd0aa055e
--- /dev/null
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/apis/__init__.py
@@ -0,0 +1,21 @@
+# coding: utf-8
+
+# flake8: noqa
+
+# import all apis into this package
+# if you have many ampis here with many many models used in each api this may
+# raise a RecursionError
+# to avoid this, import only the api that you directly need like:
+# from .api.pet_api import PetApi
+# or import this package, but before doing it, use:
+# import sys
+# sys.setrecursionlimit(n)
+
+# import apis into api package
+from petstore_api.api.another_fake_api import AnotherFakeApi
+from petstore_api.api.default_api import DefaultApi
+from petstore_api.api.fake_api import FakeApi
+from petstore_api.api.fake_classname_tags_123_api import FakeClassnameTags123Api
+from petstore_api.api.pet_api import PetApi
+from petstore_api.api.store_api import StoreApi
+from petstore_api.api.user_api import UserApi
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/__init__.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/__init__.py
new file mode 100644
index 000000000000..cfe32b784926
--- /dev/null
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/__init__.py
@@ -0,0 +1,5 @@
+# we can not import model classes here because that would create a circular
+# reference which would not work in python2
+# do not import all models into this module because that uses a lot of memory and stack frames
+# if you need the ability to import all models from one package, import them with
+# from {{packageName}.models import ModelA, ModelB
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/additional_properties_class.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/additional_properties_class.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/additional_properties_class.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/additional_properties_class.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/address.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/address.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/address.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/address.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/animal.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/animal.py
similarity index 97%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/animal.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/animal.py
index 641c9c16e279..7ba62dad1622 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/animal.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/animal.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import cat
+    from petstore_api.model import cat
 except ImportError:
     cat = sys.modules[
-        'petstore_api.models.cat']
+        'petstore_api.model.cat']
 try:
-    from petstore_api.models import dog
+    from petstore_api.model import dog
 except ImportError:
     dog = sys.modules[
-        'petstore_api.models.dog']
+        'petstore_api.model.dog']
 
 
 class Animal(ModelNormal):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/api_response.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/api_response.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/api_response.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/api_response.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/apple.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/apple.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/apple.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/apple.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/apple_req.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/apple_req.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/apple_req.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/apple_req.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/array_of_array_of_number_only.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/array_of_array_of_number_only.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/array_of_array_of_number_only.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/array_of_array_of_number_only.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/array_of_number_only.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/array_of_number_only.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/array_of_number_only.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/array_of_number_only.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/array_test.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/array_test.py
similarity index 98%
rename from samples/client/petstore/python-experimental/petstore_api/models/array_test.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/array_test.py
index 0eed8d054611..e2bc76832b27 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/array_test.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/array_test.py
@@ -34,10 +34,10 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import read_only_first
+    from petstore_api.model import read_only_first
 except ImportError:
     read_only_first = sys.modules[
-        'petstore_api.models.read_only_first']
+        'petstore_api.model.read_only_first']
 
 
 class ArrayTest(ModelNormal):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/banana.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/banana.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/banana.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/banana.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/banana_req.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/banana_req.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/banana_req.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/banana_req.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/basque_pig.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/basque_pig.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/basque_pig.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/basque_pig.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/capitalization.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/capitalization.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/capitalization.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/capitalization.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/cat.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/cat.py
similarity index 97%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/cat.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/cat.py
index b80672252538..ab01b1f0a9c5 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/cat.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/cat.py
@@ -34,20 +34,20 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import address
+    from petstore_api.model import address
 except ImportError:
     address = sys.modules[
-        'petstore_api.models.address']
+        'petstore_api.model.address']
 try:
-    from petstore_api.models import animal
+    from petstore_api.model import animal
 except ImportError:
     animal = sys.modules[
-        'petstore_api.models.animal']
+        'petstore_api.model.animal']
 try:
-    from petstore_api.models import cat_all_of
+    from petstore_api.model import cat_all_of
 except ImportError:
     cat_all_of = sys.modules[
-        'petstore_api.models.cat_all_of']
+        'petstore_api.model.cat_all_of']
 
 
 class Cat(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/cat_all_of.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/cat_all_of.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/cat_all_of.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/cat_all_of.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/category.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/category.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/category.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/category.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/child_cat.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/child_cat.py
similarity index 97%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/child_cat.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/child_cat.py
index f838e61b4014..996f3e0098e2 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/child_cat.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/child_cat.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import child_cat_all_of
+    from petstore_api.model import child_cat_all_of
 except ImportError:
     child_cat_all_of = sys.modules[
-        'petstore_api.models.child_cat_all_of']
+        'petstore_api.model.child_cat_all_of']
 try:
-    from petstore_api.models import parent_pet
+    from petstore_api.model import parent_pet
 except ImportError:
     parent_pet = sys.modules[
-        'petstore_api.models.parent_pet']
+        'petstore_api.model.parent_pet']
 
 
 class ChildCat(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/child_cat_all_of.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/child_cat_all_of.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/child_cat_all_of.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/child_cat_all_of.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/class_model.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/class_model.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/class_model.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/class_model.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/client.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/client.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/client.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/client.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/complex_quadrilateral.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/complex_quadrilateral.py
similarity index 97%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/complex_quadrilateral.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/complex_quadrilateral.py
index 03497b55fb45..7cc5a70032a0 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/complex_quadrilateral.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/complex_quadrilateral.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import quadrilateral_interface
+    from petstore_api.model import quadrilateral_interface
 except ImportError:
     quadrilateral_interface = sys.modules[
-        'petstore_api.models.quadrilateral_interface']
+        'petstore_api.model.quadrilateral_interface']
 try:
-    from petstore_api.models import shape_interface
+    from petstore_api.model import shape_interface
 except ImportError:
     shape_interface = sys.modules[
-        'petstore_api.models.shape_interface']
+        'petstore_api.model.shape_interface']
 
 
 class ComplexQuadrilateral(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/danish_pig.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/danish_pig.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/danish_pig.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/danish_pig.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/dog.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/dog.py
similarity index 98%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/dog.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/dog.py
index e35c52bd69d0..a100eb3c70ef 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/dog.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/dog.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import animal
+    from petstore_api.model import animal
 except ImportError:
     animal = sys.modules[
-        'petstore_api.models.animal']
+        'petstore_api.model.animal']
 try:
-    from petstore_api.models import dog_all_of
+    from petstore_api.model import dog_all_of
 except ImportError:
     dog_all_of = sys.modules[
-        'petstore_api.models.dog_all_of']
+        'petstore_api.model.dog_all_of']
 
 
 class Dog(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/dog_all_of.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/dog_all_of.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/dog_all_of.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/dog_all_of.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/drawing.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/drawing.py
similarity index 95%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/drawing.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/drawing.py
index a9cf39773d6b..8d61b20887d1 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/drawing.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/drawing.py
@@ -34,25 +34,25 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import fruit
+    from petstore_api.model import fruit
 except ImportError:
     fruit = sys.modules[
-        'petstore_api.models.fruit']
+        'petstore_api.model.fruit']
 try:
-    from petstore_api.models import nullable_shape
+    from petstore_api.model import nullable_shape
 except ImportError:
     nullable_shape = sys.modules[
-        'petstore_api.models.nullable_shape']
+        'petstore_api.model.nullable_shape']
 try:
-    from petstore_api.models import shape
+    from petstore_api.model import shape
 except ImportError:
     shape = sys.modules[
-        'petstore_api.models.shape']
+        'petstore_api.model.shape']
 try:
-    from petstore_api.models import shape_or_null
+    from petstore_api.model import shape_or_null
 except ImportError:
     shape_or_null = sys.modules[
-        'petstore_api.models.shape_or_null']
+        'petstore_api.model.shape_or_null']
 
 
 class Drawing(ModelNormal):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/enum_arrays.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/enum_arrays.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/enum_arrays.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/enum_arrays.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/enum_class.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/enum_class.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/enum_class.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/enum_class.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/enum_test.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/enum_test.py
similarity index 95%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/enum_test.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/enum_test.py
index ba6118114b07..1320cc416e7d 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/enum_test.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/enum_test.py
@@ -34,25 +34,25 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import outer_enum
+    from petstore_api.model import outer_enum
 except ImportError:
     outer_enum = sys.modules[
-        'petstore_api.models.outer_enum']
+        'petstore_api.model.outer_enum']
 try:
-    from petstore_api.models import outer_enum_default_value
+    from petstore_api.model import outer_enum_default_value
 except ImportError:
     outer_enum_default_value = sys.modules[
-        'petstore_api.models.outer_enum_default_value']
+        'petstore_api.model.outer_enum_default_value']
 try:
-    from petstore_api.models import outer_enum_integer
+    from petstore_api.model import outer_enum_integer
 except ImportError:
     outer_enum_integer = sys.modules[
-        'petstore_api.models.outer_enum_integer']
+        'petstore_api.model.outer_enum_integer']
 try:
-    from petstore_api.models import outer_enum_integer_default_value
+    from petstore_api.model import outer_enum_integer_default_value
 except ImportError:
     outer_enum_integer_default_value = sys.modules[
-        'petstore_api.models.outer_enum_integer_default_value']
+        'petstore_api.model.outer_enum_integer_default_value']
 
 
 class EnumTest(ModelNormal):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/equilateral_triangle.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/equilateral_triangle.py
similarity index 97%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/equilateral_triangle.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/equilateral_triangle.py
index c601d01dde7f..44f69a5dced7 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/equilateral_triangle.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/equilateral_triangle.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import shape_interface
+    from petstore_api.model import shape_interface
 except ImportError:
     shape_interface = sys.modules[
-        'petstore_api.models.shape_interface']
+        'petstore_api.model.shape_interface']
 try:
-    from petstore_api.models import triangle_interface
+    from petstore_api.model import triangle_interface
 except ImportError:
     triangle_interface = sys.modules[
-        'petstore_api.models.triangle_interface']
+        'petstore_api.model.triangle_interface']
 
 
 class EquilateralTriangle(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/file.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/file.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/file.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/file.py
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/file_schema_test_class.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/file_schema_test_class.py
similarity index 98%
rename from samples/client/petstore/python-experimental/petstore_api/models/file_schema_test_class.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/file_schema_test_class.py
index 79e5638ccc94..0a9471e9e420 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/file_schema_test_class.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/file_schema_test_class.py
@@ -34,10 +34,10 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import file
+    from petstore_api.model import file
 except ImportError:
     file = sys.modules[
-        'petstore_api.models.file']
+        'petstore_api.model.file']
 
 
 class FileSchemaTestClass(ModelNormal):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/foo.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/foo.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/foo.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/foo.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/format_test.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/format_test.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/format_test.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/format_test.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/fruit.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/fruit.py
similarity index 98%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/fruit.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/fruit.py
index 1058c953ee60..244497b64a10 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/fruit.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/fruit.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import apple
+    from petstore_api.model import apple
 except ImportError:
     apple = sys.modules[
-        'petstore_api.models.apple']
+        'petstore_api.model.apple']
 try:
-    from petstore_api.models import banana
+    from petstore_api.model import banana
 except ImportError:
     banana = sys.modules[
-        'petstore_api.models.banana']
+        'petstore_api.model.banana']
 
 
 class Fruit(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/fruit_req.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/fruit_req.py
similarity index 98%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/fruit_req.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/fruit_req.py
index b8af0f35f432..11a7615749cc 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/fruit_req.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/fruit_req.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import apple_req
+    from petstore_api.model import apple_req
 except ImportError:
     apple_req = sys.modules[
-        'petstore_api.models.apple_req']
+        'petstore_api.model.apple_req']
 try:
-    from petstore_api.models import banana_req
+    from petstore_api.model import banana_req
 except ImportError:
     banana_req = sys.modules[
-        'petstore_api.models.banana_req']
+        'petstore_api.model.banana_req']
 
 
 class FruitReq(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/gm_fruit.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/gm_fruit.py
similarity index 98%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/gm_fruit.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/gm_fruit.py
index 9857b08c36c6..e2ebe6fd9d17 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/gm_fruit.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/gm_fruit.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import apple
+    from petstore_api.model import apple
 except ImportError:
     apple = sys.modules[
-        'petstore_api.models.apple']
+        'petstore_api.model.apple']
 try:
-    from petstore_api.models import banana
+    from petstore_api.model import banana
 except ImportError:
     banana = sys.modules[
-        'petstore_api.models.banana']
+        'petstore_api.model.banana']
 
 
 class GmFruit(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/grandparent_animal.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/grandparent_animal.py
similarity index 97%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/grandparent_animal.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/grandparent_animal.py
index ab2ba56caf37..b5af666f7530 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/grandparent_animal.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/grandparent_animal.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import child_cat
+    from petstore_api.model import child_cat
 except ImportError:
     child_cat = sys.modules[
-        'petstore_api.models.child_cat']
+        'petstore_api.model.child_cat']
 try:
-    from petstore_api.models import parent_pet
+    from petstore_api.model import parent_pet
 except ImportError:
     parent_pet = sys.modules[
-        'petstore_api.models.parent_pet']
+        'petstore_api.model.parent_pet']
 
 
 class GrandparentAnimal(ModelNormal):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/has_only_read_only.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/has_only_read_only.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/has_only_read_only.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/has_only_read_only.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/health_check_result.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/health_check_result.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/health_check_result.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/health_check_result.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/inline_object.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/inline_object.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/inline_object.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/inline_object.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/inline_object1.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/inline_object1.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/inline_object1.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/inline_object1.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/inline_object2.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/inline_object2.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/inline_object2.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/inline_object2.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/inline_object3.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/inline_object3.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/inline_object3.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/inline_object3.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/inline_object4.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/inline_object4.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/inline_object4.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/inline_object4.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/inline_object5.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/inline_object5.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/inline_object5.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/inline_object5.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/inline_response_default.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/inline_response_default.py
similarity index 98%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/inline_response_default.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/inline_response_default.py
index 577dbfeb8517..f3abf4a7a193 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/inline_response_default.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/inline_response_default.py
@@ -34,10 +34,10 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import foo
+    from petstore_api.model import foo
 except ImportError:
     foo = sys.modules[
-        'petstore_api.models.foo']
+        'petstore_api.model.foo']
 
 
 class InlineResponseDefault(ModelNormal):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/isosceles_triangle.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/isosceles_triangle.py
similarity index 97%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/isosceles_triangle.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/isosceles_triangle.py
index ea5607fdfd9b..40c8878bb003 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/isosceles_triangle.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/isosceles_triangle.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import shape_interface
+    from petstore_api.model import shape_interface
 except ImportError:
     shape_interface = sys.modules[
-        'petstore_api.models.shape_interface']
+        'petstore_api.model.shape_interface']
 try:
-    from petstore_api.models import triangle_interface
+    from petstore_api.model import triangle_interface
 except ImportError:
     triangle_interface = sys.modules[
-        'petstore_api.models.triangle_interface']
+        'petstore_api.model.triangle_interface']
 
 
 class IsoscelesTriangle(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/list.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/list.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/list.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/list.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/mammal.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/mammal.py
similarity index 97%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/mammal.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/mammal.py
index 44f3e402c981..e0b9f314080d 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/mammal.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/mammal.py
@@ -34,20 +34,20 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import pig
+    from petstore_api.model import pig
 except ImportError:
     pig = sys.modules[
-        'petstore_api.models.pig']
+        'petstore_api.model.pig']
 try:
-    from petstore_api.models import whale
+    from petstore_api.model import whale
 except ImportError:
     whale = sys.modules[
-        'petstore_api.models.whale']
+        'petstore_api.model.whale']
 try:
-    from petstore_api.models import zebra
+    from petstore_api.model import zebra
 except ImportError:
     zebra = sys.modules[
-        'petstore_api.models.zebra']
+        'petstore_api.model.zebra']
 
 
 class Mammal(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/map_test.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/map_test.py
similarity index 98%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/map_test.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/map_test.py
index 45be8a1fecfd..a22af06ce4fd 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/map_test.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/map_test.py
@@ -34,10 +34,10 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import string_boolean_map
+    from petstore_api.model import string_boolean_map
 except ImportError:
     string_boolean_map = sys.modules[
-        'petstore_api.models.string_boolean_map']
+        'petstore_api.model.string_boolean_map']
 
 
 class MapTest(ModelNormal):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/mixed_properties_and_additional_properties_class.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/mixed_properties_and_additional_properties_class.py
similarity index 98%
rename from samples/client/petstore/python-experimental/petstore_api/models/mixed_properties_and_additional_properties_class.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/mixed_properties_and_additional_properties_class.py
index 0e584ebd43e9..a0fcac2eb019 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/mixed_properties_and_additional_properties_class.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/mixed_properties_and_additional_properties_class.py
@@ -34,10 +34,10 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import animal
+    from petstore_api.model import animal
 except ImportError:
     animal = sys.modules[
-        'petstore_api.models.animal']
+        'petstore_api.model.animal']
 
 
 class MixedPropertiesAndAdditionalPropertiesClass(ModelNormal):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/model200_response.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/model200_response.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/model200_response.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/model200_response.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/model_return.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/model_return.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/model_return.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/model_return.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/name.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/name.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/name.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/name.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/nullable_class.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/nullable_class.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/nullable_class.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/nullable_class.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/nullable_shape.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/nullable_shape.py
similarity index 98%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/nullable_shape.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/nullable_shape.py
index e62a3881c520..77778126a6f7 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/nullable_shape.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/nullable_shape.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import quadrilateral
+    from petstore_api.model import quadrilateral
 except ImportError:
     quadrilateral = sys.modules[
-        'petstore_api.models.quadrilateral']
+        'petstore_api.model.quadrilateral']
 try:
-    from petstore_api.models import triangle
+    from petstore_api.model import triangle
 except ImportError:
     triangle = sys.modules[
-        'petstore_api.models.triangle']
+        'petstore_api.model.triangle']
 
 
 class NullableShape(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/number_only.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/number_only.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/number_only.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/number_only.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/order.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/order.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/order.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/order.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/outer_composite.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/outer_composite.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/outer_composite.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/outer_composite.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/outer_enum.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/outer_enum.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/outer_enum.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/outer_enum.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/outer_enum_default_value.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/outer_enum_default_value.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/outer_enum_default_value.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/outer_enum_default_value.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/outer_enum_integer.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/outer_enum_integer.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/outer_enum_integer.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/outer_enum_integer.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/outer_enum_integer_default_value.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/outer_enum_integer_default_value.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/outer_enum_integer_default_value.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/outer_enum_integer_default_value.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/parent_pet.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/parent_pet.py
similarity index 97%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/parent_pet.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/parent_pet.py
index 89633120977e..26a44926fa3e 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/parent_pet.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/parent_pet.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import child_cat
+    from petstore_api.model import child_cat
 except ImportError:
     child_cat = sys.modules[
-        'petstore_api.models.child_cat']
+        'petstore_api.model.child_cat']
 try:
-    from petstore_api.models import grandparent_animal
+    from petstore_api.model import grandparent_animal
 except ImportError:
     grandparent_animal = sys.modules[
-        'petstore_api.models.grandparent_animal']
+        'petstore_api.model.grandparent_animal']
 
 
 class ParentPet(ModelComposed):
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/pet.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/pet.py
similarity index 97%
rename from samples/client/petstore/python-experimental/petstore_api/models/pet.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/pet.py
index c93acd53c96c..742d7cdf04a8 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/pet.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/pet.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import category
+    from petstore_api.model import category
 except ImportError:
     category = sys.modules[
-        'petstore_api.models.category']
+        'petstore_api.model.category']
 try:
-    from petstore_api.models import tag
+    from petstore_api.model import tag
 except ImportError:
     tag = sys.modules[
-        'petstore_api.models.tag']
+        'petstore_api.model.tag']
 
 
 class Pet(ModelNormal):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/pig.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/pig.py
similarity index 98%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/pig.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/pig.py
index 5dd3fdb64ec1..2e02e4e88c98 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/pig.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/pig.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import basque_pig
+    from petstore_api.model import basque_pig
 except ImportError:
     basque_pig = sys.modules[
-        'petstore_api.models.basque_pig']
+        'petstore_api.model.basque_pig']
 try:
-    from petstore_api.models import danish_pig
+    from petstore_api.model import danish_pig
 except ImportError:
     danish_pig = sys.modules[
-        'petstore_api.models.danish_pig']
+        'petstore_api.model.danish_pig']
 
 
 class Pig(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/quadrilateral.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/quadrilateral.py
similarity index 97%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/quadrilateral.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/quadrilateral.py
index 0f4994064571..b0766c987164 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/quadrilateral.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/quadrilateral.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import complex_quadrilateral
+    from petstore_api.model import complex_quadrilateral
 except ImportError:
     complex_quadrilateral = sys.modules[
-        'petstore_api.models.complex_quadrilateral']
+        'petstore_api.model.complex_quadrilateral']
 try:
-    from petstore_api.models import simple_quadrilateral
+    from petstore_api.model import simple_quadrilateral
 except ImportError:
     simple_quadrilateral = sys.modules[
-        'petstore_api.models.simple_quadrilateral']
+        'petstore_api.model.simple_quadrilateral']
 
 
 class Quadrilateral(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/quadrilateral_interface.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/quadrilateral_interface.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/quadrilateral_interface.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/quadrilateral_interface.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/read_only_first.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/read_only_first.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/read_only_first.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/read_only_first.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/scalene_triangle.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/scalene_triangle.py
similarity index 97%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/scalene_triangle.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/scalene_triangle.py
index 6350bdea3bc5..2c58f1bb99ae 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/scalene_triangle.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/scalene_triangle.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import shape_interface
+    from petstore_api.model import shape_interface
 except ImportError:
     shape_interface = sys.modules[
-        'petstore_api.models.shape_interface']
+        'petstore_api.model.shape_interface']
 try:
-    from petstore_api.models import triangle_interface
+    from petstore_api.model import triangle_interface
 except ImportError:
     triangle_interface = sys.modules[
-        'petstore_api.models.triangle_interface']
+        'petstore_api.model.triangle_interface']
 
 
 class ScaleneTriangle(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/shape.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/shape.py
similarity index 98%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/shape.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/shape.py
index ef83ed3a31b7..9eec4b7705ed 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/shape.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/shape.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import quadrilateral
+    from petstore_api.model import quadrilateral
 except ImportError:
     quadrilateral = sys.modules[
-        'petstore_api.models.quadrilateral']
+        'petstore_api.model.quadrilateral']
 try:
-    from petstore_api.models import triangle
+    from petstore_api.model import triangle
 except ImportError:
     triangle = sys.modules[
-        'petstore_api.models.triangle']
+        'petstore_api.model.triangle']
 
 
 class Shape(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/shape_interface.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/shape_interface.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/shape_interface.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/shape_interface.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/shape_or_null.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/shape_or_null.py
similarity index 98%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/shape_or_null.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/shape_or_null.py
index 53043fdd60c4..8c00f44dfaac 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/shape_or_null.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/shape_or_null.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import quadrilateral
+    from petstore_api.model import quadrilateral
 except ImportError:
     quadrilateral = sys.modules[
-        'petstore_api.models.quadrilateral']
+        'petstore_api.model.quadrilateral']
 try:
-    from petstore_api.models import triangle
+    from petstore_api.model import triangle
 except ImportError:
     triangle = sys.modules[
-        'petstore_api.models.triangle']
+        'petstore_api.model.triangle']
 
 
 class ShapeOrNull(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/simple_quadrilateral.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/simple_quadrilateral.py
similarity index 97%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/simple_quadrilateral.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/simple_quadrilateral.py
index 8d8cf85fca1e..dd27bd66fea7 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/simple_quadrilateral.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/simple_quadrilateral.py
@@ -34,15 +34,15 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import quadrilateral_interface
+    from petstore_api.model import quadrilateral_interface
 except ImportError:
     quadrilateral_interface = sys.modules[
-        'petstore_api.models.quadrilateral_interface']
+        'petstore_api.model.quadrilateral_interface']
 try:
-    from petstore_api.models import shape_interface
+    from petstore_api.model import shape_interface
 except ImportError:
     shape_interface = sys.modules[
-        'petstore_api.models.shape_interface']
+        'petstore_api.model.shape_interface']
 
 
 class SimpleQuadrilateral(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/special_model_name.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/special_model_name.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/special_model_name.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/special_model_name.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/string_boolean_map.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/string_boolean_map.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/string_boolean_map.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/string_boolean_map.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/tag.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/tag.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/tag.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/tag.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/triangle.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/triangle.py
similarity index 96%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/triangle.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/triangle.py
index 27b8ae122733..52c3218db1e3 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/triangle.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/triangle.py
@@ -34,20 +34,20 @@
     validate_get_composed_info,
 )
 try:
-    from petstore_api.models import equilateral_triangle
+    from petstore_api.model import equilateral_triangle
 except ImportError:
     equilateral_triangle = sys.modules[
-        'petstore_api.models.equilateral_triangle']
+        'petstore_api.model.equilateral_triangle']
 try:
-    from petstore_api.models import isosceles_triangle
+    from petstore_api.model import isosceles_triangle
 except ImportError:
     isosceles_triangle = sys.modules[
-        'petstore_api.models.isosceles_triangle']
+        'petstore_api.model.isosceles_triangle']
 try:
-    from petstore_api.models import scalene_triangle
+    from petstore_api.model import scalene_triangle
 except ImportError:
     scalene_triangle = sys.modules[
-        'petstore_api.models.scalene_triangle']
+        'petstore_api.model.scalene_triangle']
 
 
 class Triangle(ModelComposed):
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/triangle_interface.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/triangle_interface.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/triangle_interface.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/triangle_interface.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/user.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/user.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/user.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/user.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/whale.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/whale.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/whale.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/whale.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/zebra.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/zebra.py
similarity index 100%
rename from samples/openapi3/client/petstore/python-experimental/petstore_api/models/zebra.py
rename to samples/openapi3/client/petstore/python-experimental/petstore_api/model/zebra.py
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/__init__.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/models/__init__.py
index e02c66519259..7c58ced9f86a 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/__init__.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/models/__init__.py
@@ -1,15 +1,95 @@
 # coding: utf-8
 
 # flake8: noqa
-"""
-    OpenAPI Petstore
 
-    This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
+# import all models into this package
+# if you have many models here with many references from one model to another this may
+# raise a RecursionError
+# to avoid this, import only the models that you directly need like:
+# from from petstore_api.model.pet import Pet
+# or import this package, but before doing it, use:
+# import sys
+# sys.setrecursionlimit(n)
 
-    The version of the OpenAPI document: 1.0.0
-    Generated by: https://openapi-generator.tech
-"""
-
-
-# we can not import model classes here because that would create a circular
-# reference which would not work in python2
+from petstore_api.model.additional_properties_class import AdditionalPropertiesClass
+from petstore_api.model.address import Address
+from petstore_api.model.animal import Animal
+from petstore_api.model.api_response import ApiResponse
+from petstore_api.model.apple import Apple
+from petstore_api.model.apple_req import AppleReq
+from petstore_api.model.array_of_array_of_number_only import ArrayOfArrayOfNumberOnly
+from petstore_api.model.array_of_number_only import ArrayOfNumberOnly
+from petstore_api.model.array_test import ArrayTest
+from petstore_api.model.banana import Banana
+from petstore_api.model.banana_req import BananaReq
+from petstore_api.model.basque_pig import BasquePig
+from petstore_api.model.capitalization import Capitalization
+from petstore_api.model.cat import Cat
+from petstore_api.model.cat_all_of import CatAllOf
+from petstore_api.model.category import Category
+from petstore_api.model.child_cat import ChildCat
+from petstore_api.model.child_cat_all_of import ChildCatAllOf
+from petstore_api.model.class_model import ClassModel
+from petstore_api.model.client import Client
+from petstore_api.model.complex_quadrilateral import ComplexQuadrilateral
+from petstore_api.model.danish_pig import DanishPig
+from petstore_api.model.dog import Dog
+from petstore_api.model.dog_all_of import DogAllOf
+from petstore_api.model.drawing import Drawing
+from petstore_api.model.enum_arrays import EnumArrays
+from petstore_api.model.enum_class import EnumClass
+from petstore_api.model.enum_test import EnumTest
+from petstore_api.model.equilateral_triangle import EquilateralTriangle
+from petstore_api.model.file import File
+from petstore_api.model.file_schema_test_class import FileSchemaTestClass
+from petstore_api.model.foo import Foo
+from petstore_api.model.format_test import FormatTest
+from petstore_api.model.fruit import Fruit
+from petstore_api.model.fruit_req import FruitReq
+from petstore_api.model.gm_fruit import GmFruit
+from petstore_api.model.grandparent_animal import GrandparentAnimal
+from petstore_api.model.has_only_read_only import HasOnlyReadOnly
+from petstore_api.model.health_check_result import HealthCheckResult
+from petstore_api.model.inline_object import InlineObject
+from petstore_api.model.inline_object1 import InlineObject1
+from petstore_api.model.inline_object2 import InlineObject2
+from petstore_api.model.inline_object3 import InlineObject3
+from petstore_api.model.inline_object4 import InlineObject4
+from petstore_api.model.inline_object5 import InlineObject5
+from petstore_api.model.inline_response_default import InlineResponseDefault
+from petstore_api.model.isosceles_triangle import IsoscelesTriangle
+from petstore_api.model.list import List
+from petstore_api.model.mammal import Mammal
+from petstore_api.model.map_test import MapTest
+from petstore_api.model.mixed_properties_and_additional_properties_class import MixedPropertiesAndAdditionalPropertiesClass
+from petstore_api.model.model200_response import Model200Response
+from petstore_api.model.model_return import ModelReturn
+from petstore_api.model.name import Name
+from petstore_api.model.nullable_class import NullableClass
+from petstore_api.model.nullable_shape import NullableShape
+from petstore_api.model.number_only import NumberOnly
+from petstore_api.model.order import Order
+from petstore_api.model.outer_composite import OuterComposite
+from petstore_api.model.outer_enum import OuterEnum
+from petstore_api.model.outer_enum_default_value import OuterEnumDefaultValue
+from petstore_api.model.outer_enum_integer import OuterEnumInteger
+from petstore_api.model.outer_enum_integer_default_value import OuterEnumIntegerDefaultValue
+from petstore_api.model.parent_pet import ParentPet
+from petstore_api.model.pet import Pet
+from petstore_api.model.pig import Pig
+from petstore_api.model.quadrilateral import Quadrilateral
+from petstore_api.model.quadrilateral_interface import QuadrilateralInterface
+from petstore_api.model.read_only_first import ReadOnlyFirst
+from petstore_api.model.scalene_triangle import ScaleneTriangle
+from petstore_api.model.shape import Shape
+from petstore_api.model.shape_interface import ShapeInterface
+from petstore_api.model.shape_or_null import ShapeOrNull
+from petstore_api.model.simple_quadrilateral import SimpleQuadrilateral
+from petstore_api.model.special_model_name import SpecialModelName
+from petstore_api.model.string_boolean_map import StringBooleanMap
+from petstore_api.model.tag import Tag
+from petstore_api.model.triangle import Triangle
+from petstore_api.model.triangle_interface import TriangleInterface
+from petstore_api.model.user import User
+from petstore_api.model.whale import Whale
+from petstore_api.model.zebra import Zebra
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/gm_mammal.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/models/gm_mammal.py
deleted file mode 100644
index 40d056a494ec..000000000000
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/models/gm_mammal.py
+++ /dev/null
@@ -1,212 +0,0 @@
-# coding: utf-8
-
-"""
-    OpenAPI Petstore
-
-    This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\  # noqa: E501
-
-    The version of the OpenAPI document: 1.0.0
-    Generated by: https://openapi-generator.tech
-"""
-
-
-from __future__ import absolute_import
-import re  # noqa: F401
-import sys  # noqa: F401
-
-import six  # noqa: F401
-
-from petstore_api.model_utils import (  # noqa: F401
-    ModelComposed,
-    ModelNormal,
-    ModelSimple,
-    date,
-    datetime,
-    file_type,
-    int,
-    none_type,
-    str,
-    validate_get_composed_info,
-)
-try:
-    from petstore_api.models import whale
-except ImportError:
-    whale = sys.modules[
-        'petstore_api.models.whale']
-try:
-    from petstore_api.models import zebra
-except ImportError:
-    zebra = sys.modules[
-        'petstore_api.models.zebra']
-
-
-class GmMammal(ModelComposed):
-    """NOTE: This class is auto generated by OpenAPI Generator.
-    Ref: https://openapi-generator.tech
-
-    Do not edit the class manually.
-
-    Attributes:
-      allowed_values (dict): The key is the tuple path to the attribute
-          and the for var_name this is (var_name,). The value is a dict
-          with a capitalized key describing the allowed value and an allowed
-          value. These dicts store the allowed enum values.
-      attribute_map (dict): The key is attribute name
-          and the value is json key in definition.
-      discriminator_value_class_map (dict): A dict to go from the discriminator
-          variable value to the discriminator class name.
-      validations (dict): The key is the tuple path to the attribute
-          and the for var_name this is (var_name,). The value is a dict
-          that stores validations for max_length, min_length, max_items,
-          min_items, exclusive_maximum, inclusive_maximum, exclusive_minimum,
-          inclusive_minimum, and regex.
-      additional_properties_type (tuple): A tuple of classes accepted
-          as additional properties values.
-    """
-
-    allowed_values = {
-        ('lungs',): {
-            '2': 2,
-        },
-        ('type',): {
-            'PLAINS': "plains",
-            'MOUNTAIN': "mountain",
-            'GREVYS': "grevys",
-        },
-    }
-
-    validations = {
-    }
-
-    additional_properties_type = None
-
-    @staticmethod
-    def openapi_types():
-        """
-        This must be a class method so a model may have properties that are
-        of type self, this ensures that we don't create a cyclic import
-
-        Returns
-            openapi_types (dict): The key is attribute name
-                and the value is attribute type.
-        """
-        return {
-            'class_name': (str,),  # noqa: E501
-            'lungs': (int,),  # noqa: E501
-            'has_baleen': (bool,),  # noqa: E501
-            'has_teeth': (bool,),  # noqa: E501
-            'type': (str,),  # noqa: E501
-        }
-
-    @staticmethod
-    def discriminator():
-        return {
-            'class_name': {
-                'whale': whale.Whale,
-                'zebra': zebra.Zebra,
-            },
-        }
-
-    attribute_map = {
-        'class_name': 'className',  # noqa: E501
-        'lungs': 'lungs',  # noqa: E501
-        'has_baleen': 'hasBaleen',  # noqa: E501
-        'has_teeth': 'hasTeeth',  # noqa: E501
-        'type': 'type',  # noqa: E501
-    }
-
-    required_properties = set([
-        '_data_store',
-        '_check_type',
-        '_json_variable_naming',
-        '_path_to_item',
-        '_configuration',
-        '_composed_instances',
-        '_var_name_to_model_instances',
-        '_additional_properties_model_instances',
-    ])
-
-    def __init__(self, class_name, _check_type=True, _json_variable_naming=False, _path_to_item=(), _configuration=None, **kwargs):  # noqa: E501
-        """gm_mammal.GmMammal - a model defined in OpenAPI
-
-        Args:
-            class_name (str):
-
-        Keyword Args:
-            _check_type (bool): if True, values for parameters in openapi_types
-                                will be type checked and a TypeError will be
-                                raised if the wrong type is input.
-                                Defaults to True
-            _path_to_item (tuple/list): This is a list of keys or values to
-                                drill down to the model in received_data
-                                when deserializing a response
-            _json_variable_naming (bool): True if the data is from the server
-                                False if the data is from the client (default)
-            _configuration (Configuration): the instance to use when
-                                deserializing a file_type parameter.
-                                If passed, type conversion is attempted
-                                If omitted no type conversion is done.
-            lungs (int): [optional] if omitted the server will use the default value of 2  # noqa: E501
-            has_baleen (bool): [optional]  # noqa: E501
-            has_teeth (bool): [optional]  # noqa: E501
-            type (str): [optional]  # noqa: E501
-        """
-
-        self._data_store = {}
-        self._check_type = _check_type
-        self._json_variable_naming = _json_variable_naming
-        self._path_to_item = _path_to_item
-        self._configuration = _configuration
-
-        constant_args = {
-            '_check_type': _check_type,
-            '_path_to_item': _path_to_item,
-            '_json_variable_naming': _json_variable_naming,
-            '_configuration': _configuration,
-        }
-        model_args = {
-            'class_name': class_name,
-        }
-        model_args.update(kwargs)
-        composed_info = validate_get_composed_info(
-            constant_args, model_args, self)
-        self._composed_instances = composed_info[0]
-        self._var_name_to_model_instances = composed_info[1]
-        self._additional_properties_model_instances = composed_info[2]
-
-        self.class_name = class_name
-        for var_name, var_value in six.iteritems(kwargs):
-            setattr(self, var_name, var_value)
-
-    @staticmethod
-    def _composed_schemas():
-        # we need this here to make our import statements work
-        # we must store _composed_schemas in here so the code is only run
-        # when we invoke this method. If we kept this at the class
-        # level we would get an error beause the class level
-        # code would be run when this module is imported, and these composed
-        # classes don't exist yet because their module has not finished
-        # loading
-        return {
-          'anyOf': [
-              whale.Whale,
-              zebra.Zebra,
-          ],
-          'allOf': [
-          ],
-          'oneOf': [
-          ],
-        }
-
-    @classmethod
-    def get_discriminator_class(cls, json_variable_naming, data):
-        """Returns the child class specified by the discriminator"""
-        discriminator = cls.discriminator()
-        discr_propertyname_py = list(discriminator.keys())[0]
-        discr_propertyname_js = cls.attribute_map[discr_propertyname_py]
-        if json_variable_naming:
-            class_name = data[discr_propertyname_js]
-        else:
-            class_name = data[discr_propertyname_py]
-        class_name_to_discr_class = discriminator[discr_propertyname_py]
-        return class_name_to_discr_class.get(class_name)
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_additional_properties_class.py b/samples/openapi3/client/petstore/python-experimental/test/test_additional_properties_class.py
index 279baa3a454f..befc14455da2 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_additional_properties_class.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_additional_properties_class.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.additional_properties_class import AdditionalPropertiesClass
 
 
 class TestAdditionalPropertiesClass(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testAdditionalPropertiesClass(self):
         """Test AdditionalPropertiesClass"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.AdditionalPropertiesClass()  # noqa: E501
+        # model = AdditionalPropertiesClass()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_address.py b/samples/openapi3/client/petstore/python-experimental/test/test_address.py
index 7aa36d745cf5..dcc33c22dbb3 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_address.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_address.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.address import Address
 
 
 class TestAddress(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testAddress(self):
         """Test Address"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Address()  # noqa: E501
+        # model = Address()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_animal.py b/samples/openapi3/client/petstore/python-experimental/test/test_animal.py
index 66f94c5eef4e..958f303f13e3 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_animal.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_animal.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import cat
+except ImportError:
+    cat = sys.modules[
+        'petstore_api.model.cat']
+try:
+    from petstore_api.model import dog
+except ImportError:
+    dog = sys.modules[
+        'petstore_api.model.dog']
+from petstore_api.model.animal import Animal
 
 
 class TestAnimal(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testAnimal(self):
         """Test Animal"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Animal()  # noqa: E501
+        # model = Animal()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_another_fake_api.py b/samples/openapi3/client/petstore/python-experimental/test/test_another_fake_api.py
index d95798cfc5a4..f79966a26961 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_another_fake_api.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_another_fake_api.py
@@ -16,14 +16,13 @@
 
 import petstore_api
 from petstore_api.api.another_fake_api import AnotherFakeApi  # noqa: E501
-from petstore_api.rest import ApiException
 
 
 class TestAnotherFakeApi(unittest.TestCase):
     """AnotherFakeApi unit test stubs"""
 
     def setUp(self):
-        self.api = petstore_api.api.another_fake_api.AnotherFakeApi()  # noqa: E501
+        self.api = AnotherFakeApi()  # noqa: E501
 
     def tearDown(self):
         pass
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_api_response.py b/samples/openapi3/client/petstore/python-experimental/test/test_api_response.py
index a253e6f364cd..9db92633f626 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_api_response.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_api_response.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.api_response import ApiResponse
 
 
 class TestApiResponse(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testApiResponse(self):
         """Test ApiResponse"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ApiResponse()  # noqa: E501
+        # model = ApiResponse()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_apple.py b/samples/openapi3/client/petstore/python-experimental/test/test_apple.py
index 100866918919..9aedfc0b01d5 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_apple.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_apple.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.apple import Apple
 
 
 class TestApple(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testApple(self):
         """Test Apple"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Apple()  # noqa: E501
+        # model = Apple()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_apple_req.py b/samples/openapi3/client/petstore/python-experimental/test/test_apple_req.py
index 4cb5abcdede4..79650cd1c747 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_apple_req.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_apple_req.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.apple_req import AppleReq
 
 
 class TestAppleReq(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testAppleReq(self):
         """Test AppleReq"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.AppleReq()  # noqa: E501
+        # model = AppleReq()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_array_of_array_of_number_only.py b/samples/openapi3/client/petstore/python-experimental/test/test_array_of_array_of_number_only.py
index e47430f6861a..4980ad17afb5 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_array_of_array_of_number_only.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_array_of_array_of_number_only.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.array_of_array_of_number_only import ArrayOfArrayOfNumberOnly
 
 
 class TestArrayOfArrayOfNumberOnly(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testArrayOfArrayOfNumberOnly(self):
         """Test ArrayOfArrayOfNumberOnly"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ArrayOfArrayOfNumberOnly()  # noqa: E501
+        # model = ArrayOfArrayOfNumberOnly()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_array_of_number_only.py b/samples/openapi3/client/petstore/python-experimental/test/test_array_of_number_only.py
index 1a65f69b9268..479c537cada7 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_array_of_number_only.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_array_of_number_only.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.array_of_number_only import ArrayOfNumberOnly
 
 
 class TestArrayOfNumberOnly(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testArrayOfNumberOnly(self):
         """Test ArrayOfNumberOnly"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ArrayOfNumberOnly()  # noqa: E501
+        # model = ArrayOfNumberOnly()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_array_test.py b/samples/openapi3/client/petstore/python-experimental/test/test_array_test.py
index ac1b486bb74e..2426b27b7e46 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_array_test.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_array_test.py
@@ -11,10 +11,16 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import read_only_first
+except ImportError:
+    read_only_first = sys.modules[
+        'petstore_api.model.read_only_first']
+from petstore_api.model.array_test import ArrayTest
 
 
 class TestArrayTest(unittest.TestCase):
@@ -29,7 +35,7 @@ def tearDown(self):
     def testArrayTest(self):
         """Test ArrayTest"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ArrayTest()  # noqa: E501
+        # model = ArrayTest()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_banana.py b/samples/openapi3/client/petstore/python-experimental/test/test_banana.py
index 6efdcd07da1c..a989386b018c 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_banana.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_banana.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.banana import Banana
 
 
 class TestBanana(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testBanana(self):
         """Test Banana"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Banana()  # noqa: E501
+        # model = Banana()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_banana_req.py b/samples/openapi3/client/petstore/python-experimental/test/test_banana_req.py
index 5eeb0bc57c21..39d125e4a15e 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_banana_req.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_banana_req.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.banana_req import BananaReq
 
 
 class TestBananaReq(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testBananaReq(self):
         """Test BananaReq"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.BananaReq()  # noqa: E501
+        # model = BananaReq()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_basque_pig.py b/samples/openapi3/client/petstore/python-experimental/test/test_basque_pig.py
index 46e9ff215dc8..b00c5f8a6aa5 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_basque_pig.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_basque_pig.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.basque_pig import BasquePig
 
 
 class TestBasquePig(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testBasquePig(self):
         """Test BasquePig"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.BasquePig()  # noqa: E501
+        # model = BasquePig()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_capitalization.py b/samples/openapi3/client/petstore/python-experimental/test/test_capitalization.py
index 1cb91380a768..20d2649c01eb 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_capitalization.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_capitalization.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.capitalization import Capitalization
 
 
 class TestCapitalization(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testCapitalization(self):
         """Test Capitalization"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Capitalization()  # noqa: E501
+        # model = Capitalization()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_cat.py b/samples/openapi3/client/petstore/python-experimental/test/test_cat.py
index bd616261861d..1cb6b58cbd09 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_cat.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_cat.py
@@ -11,10 +11,26 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import address
+except ImportError:
+    address = sys.modules[
+        'petstore_api.model.address']
+try:
+    from petstore_api.model import animal
+except ImportError:
+    animal = sys.modules[
+        'petstore_api.model.animal']
+try:
+    from petstore_api.model import cat_all_of
+except ImportError:
+    cat_all_of = sys.modules[
+        'petstore_api.model.cat_all_of']
+from petstore_api.model.cat import Cat
 
 
 class TestCat(unittest.TestCase):
@@ -29,7 +45,7 @@ def tearDown(self):
     def testCat(self):
         """Test Cat"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Cat()  # noqa: E501
+        # model = Cat()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_cat_all_of.py b/samples/openapi3/client/petstore/python-experimental/test/test_cat_all_of.py
index 136ed8da050a..a5bb91ac864e 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_cat_all_of.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_cat_all_of.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.cat_all_of import CatAllOf
 
 
 class TestCatAllOf(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testCatAllOf(self):
         """Test CatAllOf"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.CatAllOf()  # noqa: E501
+        # model = CatAllOf()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_category.py b/samples/openapi3/client/petstore/python-experimental/test/test_category.py
index c2ab96f823b6..59b64e5924a8 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_category.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_category.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.category import Category
 
 
 class TestCategory(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testCategory(self):
         """Test Category"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Category()  # noqa: E501
+        # model = Category()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_child_cat.py b/samples/openapi3/client/petstore/python-experimental/test/test_child_cat.py
index c42c3b583aae..34c085515a80 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_child_cat.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_child_cat.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import child_cat_all_of
+except ImportError:
+    child_cat_all_of = sys.modules[
+        'petstore_api.model.child_cat_all_of']
+try:
+    from petstore_api.model import parent_pet
+except ImportError:
+    parent_pet = sys.modules[
+        'petstore_api.model.parent_pet']
+from petstore_api.model.child_cat import ChildCat
 
 
 class TestChildCat(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testChildCat(self):
         """Test ChildCat"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ChildCat()  # noqa: E501
+        # model = ChildCat()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_child_cat_all_of.py b/samples/openapi3/client/petstore/python-experimental/test/test_child_cat_all_of.py
index 3304a81a2321..2a7aab100fbf 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_child_cat_all_of.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_child_cat_all_of.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.child_cat_all_of import ChildCatAllOf
 
 
 class TestChildCatAllOf(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testChildCatAllOf(self):
         """Test ChildCatAllOf"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ChildCatAllOf()  # noqa: E501
+        # model = ChildCatAllOf()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_class_model.py b/samples/openapi3/client/petstore/python-experimental/test/test_class_model.py
index 3ac7e553042e..060df39e4b5e 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_class_model.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_class_model.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.class_model import ClassModel
 
 
 class TestClassModel(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testClassModel(self):
         """Test ClassModel"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ClassModel()  # noqa: E501
+        # model = ClassModel()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_client.py b/samples/openapi3/client/petstore/python-experimental/test/test_client.py
index 683190363445..ab5e3a80d377 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_client.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_client.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.client import Client
 
 
 class TestClient(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testClient(self):
         """Test Client"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Client()  # noqa: E501
+        # model = Client()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_complex_quadrilateral.py b/samples/openapi3/client/petstore/python-experimental/test/test_complex_quadrilateral.py
index b1d4fc9079bd..0c0887509c8b 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_complex_quadrilateral.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_complex_quadrilateral.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import quadrilateral_interface
+except ImportError:
+    quadrilateral_interface = sys.modules[
+        'petstore_api.model.quadrilateral_interface']
+try:
+    from petstore_api.model import shape_interface
+except ImportError:
+    shape_interface = sys.modules[
+        'petstore_api.model.shape_interface']
+from petstore_api.model.complex_quadrilateral import ComplexQuadrilateral
 
 
 class TestComplexQuadrilateral(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testComplexQuadrilateral(self):
         """Test ComplexQuadrilateral"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ComplexQuadrilateral()  # noqa: E501
+        # model = ComplexQuadrilateral()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_danish_pig.py b/samples/openapi3/client/petstore/python-experimental/test/test_danish_pig.py
index 0cbe8f8c102a..a82c352e84c1 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_danish_pig.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_danish_pig.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.danish_pig import DanishPig
 
 
 class TestDanishPig(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testDanishPig(self):
         """Test DanishPig"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.DanishPig()  # noqa: E501
+        # model = DanishPig()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_default_api.py b/samples/openapi3/client/petstore/python-experimental/test/test_default_api.py
index 50e7c57bd0bf..5f4fb5230ac4 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_default_api.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_default_api.py
@@ -16,14 +16,13 @@
 
 import petstore_api
 from petstore_api.api.default_api import DefaultApi  # noqa: E501
-from petstore_api.rest import ApiException
 
 
 class TestDefaultApi(unittest.TestCase):
     """DefaultApi unit test stubs"""
 
     def setUp(self):
-        self.api = petstore_api.api.default_api.DefaultApi()  # noqa: E501
+        self.api = DefaultApi()  # noqa: E501
 
     def tearDown(self):
         pass
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_dog.py b/samples/openapi3/client/petstore/python-experimental/test/test_dog.py
index 37e9dd56d4ff..4a6fc61ad761 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_dog.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_dog.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import animal
+except ImportError:
+    animal = sys.modules[
+        'petstore_api.model.animal']
+try:
+    from petstore_api.model import dog_all_of
+except ImportError:
+    dog_all_of = sys.modules[
+        'petstore_api.model.dog_all_of']
+from petstore_api.model.dog import Dog
 
 
 class TestDog(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testDog(self):
         """Test Dog"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Dog()  # noqa: E501
+        # model = Dog()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_dog_all_of.py b/samples/openapi3/client/petstore/python-experimental/test/test_dog_all_of.py
index 7f443eb9b60c..7ab4e8ae79d8 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_dog_all_of.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_dog_all_of.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.dog_all_of import DogAllOf
 
 
 class TestDogAllOf(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testDogAllOf(self):
         """Test DogAllOf"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.DogAllOf()  # noqa: E501
+        # model = DogAllOf()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_drawing.py b/samples/openapi3/client/petstore/python-experimental/test/test_drawing.py
index 6897ce82676d..dbfba3ea700f 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_drawing.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_drawing.py
@@ -11,17 +11,33 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import nullable_shape
+except ImportError:
+    nullable_shape = sys.modules[
+        'petstore_api.model.nullable_shape']
+try:
+    from petstore_api.model import shape
+except ImportError:
+    shape = sys.modules[
+        'petstore_api.model.shape']
+try:
+    from petstore_api.model import shape_or_null
+except ImportError:
+    shape_or_null = sys.modules[
+        'petstore_api.model.shape_or_null']
+from petstore_api.model.drawing import Drawing
 
 
 class TestDrawing(unittest.TestCase):
     """Drawing unit test stubs"""
 
     def setUp(self):
-        self.api_client = petstore_api.ApiClient()
+        pass
 
     def tearDown(self):
         pass
@@ -32,73 +48,79 @@ def test_create_instances(self):
         """
 
         # Validate object can be created using pythonic names.
-        inst = petstore_api.Shape(
+        inst = shape.Shape(
             shape_type="Triangle",
             triangle_type="IsoscelesTriangle"
         )
-        assert isinstance(inst, petstore_api.IsoscelesTriangle)
+        from petstore_api.model.isosceles_triangle import IsoscelesTriangle
+        assert isinstance(inst, IsoscelesTriangle)
 
         # Validate object can be created using OAS names.
         # For example, this can be used to construct objects on the client
         # when the input data is available as JSON documents.
         data =  {
-              'shapeType': "Triangle",
-              'triangleType': "IsoscelesTriangle"
+            'shapeType': "Triangle",
+            'triangleType': "IsoscelesTriangle"
         }
-        inst = petstore_api.Shape(_spec_property_naming=True, **data)
-        assert isinstance(inst, petstore_api.IsoscelesTriangle)
+        inst = shape.Shape(_spec_property_naming=True, **data)
+        assert isinstance(inst, IsoscelesTriangle)
 
     def test_deserialize_oneof_reference(self):
         """
         Validate the scenario when the type of a OAS property is 'oneOf', and the 'oneOf'
         schema is specified as a reference ($ref), not an inline 'oneOf' schema.
         """
-        isosceles_triangle = petstore_api.Shape(
+        isosceles_triangle = shape.Shape(
             shape_type="Triangle",
             triangle_type="IsoscelesTriangle"
         )
-        assert isinstance(isosceles_triangle, petstore_api.IsoscelesTriangle)
-        inst = petstore_api.Drawing(
+        from petstore_api.model.isosceles_triangle import IsoscelesTriangle
+        from petstore_api.model.triangle import Triangle
+        from petstore_api.model.equilateral_triangle import EquilateralTriangle
+
+        assert isinstance(isosceles_triangle, IsoscelesTriangle)
+        inst = Drawing(
             # 'main_shape' has type 'Shape', which is a oneOf [triangle, quadrilateral]
             # composed schema. So we should be able to assign a petstore_api.Triangle
             # to a 'main_shape'.
             main_shape=isosceles_triangle,
             shapes=[
-                petstore_api.Shape(
+                shape.Shape(
                     shape_type="Triangle",
                     triangle_type="EquilateralTriangle"
                 ),
-                petstore_api.Triangle(
+                Triangle(
                     shape_type="Triangle",
                     triangle_type="IsoscelesTriangle"
                 ),
-                petstore_api.EquilateralTriangle(
+                EquilateralTriangle(
                     shape_type="Triangle",
                     triangle_type="EquilateralTriangle"
                 ),
-                petstore_api.Shape(
+                shape.Shape(
                     shape_type="Quadrilateral",
                     quadrilateral_type="ComplexQuadrilateral"
                 ),
             ],
         )
-        assert isinstance(inst, petstore_api.Drawing)
-        assert isinstance(inst.main_shape, petstore_api.IsoscelesTriangle)
+        from petstore_api.model.complex_quadrilateral import ComplexQuadrilateral
+        assert isinstance(inst, Drawing)
+        assert isinstance(inst.main_shape, IsoscelesTriangle)
         self.assertEqual(len(inst.shapes), 4)
-        assert isinstance(inst.shapes[0], petstore_api.EquilateralTriangle)
-        assert isinstance(inst.shapes[1], petstore_api.IsoscelesTriangle)
-        assert isinstance(inst.shapes[2], petstore_api.EquilateralTriangle)
-        assert isinstance(inst.shapes[3], petstore_api.ComplexQuadrilateral)
+        assert isinstance(inst.shapes[0], EquilateralTriangle)
+        assert isinstance(inst.shapes[1], IsoscelesTriangle)
+        assert isinstance(inst.shapes[2], EquilateralTriangle)
+        assert isinstance(inst.shapes[3], ComplexQuadrilateral)
 
         # Validate we cannot assign the None value to main_shape because the 'null' type
         # is not one of the allowed types in the 'Shape' schema.
         err_msg = ("Invalid type for variable '{}'. "
-            "Required value type is {} and passed type was {} at {}")
+                   "Required value type is {} and passed type was {} at {}")
         with self.assertRaisesRegexp(
-            petstore_api.ApiTypeError,
-            err_msg.format("main_shape", "Shape", "NoneType", "\['main_shape'\]")
+                petstore_api.ApiTypeError,
+                err_msg.format("main_shape", "Shape", "NoneType", "\['main_shape'\]")
         ):
-            inst = petstore_api.Drawing(
+            inst = Drawing(
                 # 'main_shape' has type 'Shape', which is a oneOf [triangle, quadrilateral]
                 # So the None value should not be allowed and an exception should be raised.
                 main_shape=None,
@@ -115,11 +137,11 @@ def test_deserialize_oneof_reference_with_null_type(self):
 
         # Validate we can assign the None value to shape_or_null, because the 'null' type
         # is one of the allowed types in the 'ShapeOrNull' schema.
-        inst = petstore_api.Drawing(
+        inst = Drawing(
             # 'shape_or_null' has type 'ShapeOrNull', which is a oneOf [null, triangle, quadrilateral]
             shape_or_null=None,
         )
-        assert isinstance(inst, petstore_api.Drawing)
+        assert isinstance(inst, Drawing)
         self.assertFalse(hasattr(inst, 'main_shape'))
         self.assertTrue(hasattr(inst, 'shape_or_null'))
         self.assertIsNone(inst.shape_or_null)
@@ -135,16 +157,15 @@ def test_deserialize_oneof_reference_with_nullable_type(self):
 
         # Validate we can assign the None value to nullable_shape, because the NullableShape
         # has the 'nullable: true' attribute.
-        inst = petstore_api.Drawing(
+        inst = Drawing(
             # 'nullable_shape' has type 'NullableShape', which is a oneOf [triangle, quadrilateral]
-            # and the 'nullable: true' attribute. 
+            # and the 'nullable: true' attribute.
             nullable_shape=None,
         )
-        assert isinstance(inst, petstore_api.Drawing)
+        assert isinstance(inst, Drawing)
         self.assertFalse(hasattr(inst, 'main_shape'))
         self.assertTrue(hasattr(inst, 'nullable_shape'))
         self.assertIsNone(inst.nullable_shape)
 
-
 if __name__ == '__main__':
     unittest.main()
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_enum_arrays.py b/samples/openapi3/client/petstore/python-experimental/test/test_enum_arrays.py
index 5f789287332a..143a23fe0d45 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_enum_arrays.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_enum_arrays.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.enum_arrays import EnumArrays
 
 
 class TestEnumArrays(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testEnumArrays(self):
         """Test EnumArrays"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.EnumArrays()  # noqa: E501
+        # model = EnumArrays()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_enum_class.py b/samples/openapi3/client/petstore/python-experimental/test/test_enum_class.py
index f25e772ff26a..f910231c9d02 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_enum_class.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_enum_class.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.enum_class import EnumClass
 
 
 class TestEnumClass(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testEnumClass(self):
         """Test EnumClass"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.EnumClass()  # noqa: E501
+        # model = EnumClass()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_enum_test.py b/samples/openapi3/client/petstore/python-experimental/test/test_enum_test.py
index 8238fb7a3ab9..6a98e49b9689 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_enum_test.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_enum_test.py
@@ -11,10 +11,31 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import outer_enum
+except ImportError:
+    outer_enum = sys.modules[
+        'petstore_api.model.outer_enum']
+try:
+    from petstore_api.model import outer_enum_default_value
+except ImportError:
+    outer_enum_default_value = sys.modules[
+        'petstore_api.model.outer_enum_default_value']
+try:
+    from petstore_api.model import outer_enum_integer
+except ImportError:
+    outer_enum_integer = sys.modules[
+        'petstore_api.model.outer_enum_integer']
+try:
+    from petstore_api.model import outer_enum_integer_default_value
+except ImportError:
+    outer_enum_integer_default_value = sys.modules[
+        'petstore_api.model.outer_enum_integer_default_value']
+from petstore_api.model.enum_test import EnumTest
 
 
 class TestEnumTest(unittest.TestCase):
@@ -29,7 +50,7 @@ def tearDown(self):
     def testEnumTest(self):
         """Test EnumTest"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.EnumTest()  # noqa: E501
+        # model = EnumTest()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_equilateral_triangle.py b/samples/openapi3/client/petstore/python-experimental/test/test_equilateral_triangle.py
index cdef216105eb..8f286edfdcba 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_equilateral_triangle.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_equilateral_triangle.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import shape_interface
+except ImportError:
+    shape_interface = sys.modules[
+        'petstore_api.model.shape_interface']
+try:
+    from petstore_api.model import triangle_interface
+except ImportError:
+    triangle_interface = sys.modules[
+        'petstore_api.model.triangle_interface']
+from petstore_api.model.equilateral_triangle import EquilateralTriangle
 
 
 class TestEquilateralTriangle(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testEquilateralTriangle(self):
         """Test EquilateralTriangle"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.EquilateralTriangle()  # noqa: E501
+        # model = EquilateralTriangle()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_fake_api.py b/samples/openapi3/client/petstore/python-experimental/test/test_fake_api.py
index 581d1499eedf..f6678a59b240 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_fake_api.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_fake_api.py
@@ -16,14 +16,13 @@
 
 import petstore_api
 from petstore_api.api.fake_api import FakeApi  # noqa: E501
-from petstore_api.rest import ApiException
 
 
 class TestFakeApi(unittest.TestCase):
     """FakeApi unit test stubs"""
 
     def setUp(self):
-        self.api = petstore_api.api.fake_api.FakeApi()  # noqa: E501
+        self.api = FakeApi()  # noqa: E501
 
     def tearDown(self):
         pass
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_fake_classname_tags_123_api.py b/samples/openapi3/client/petstore/python-experimental/test/test_fake_classname_tags_123_api.py
index f54e0d06644f..c12e35eb5dea 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_fake_classname_tags_123_api.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_fake_classname_tags_123_api.py
@@ -16,14 +16,13 @@
 
 import petstore_api
 from petstore_api.api.fake_classname_tags_123_api import FakeClassnameTags123Api  # noqa: E501
-from petstore_api.rest import ApiException
 
 
 class TestFakeClassnameTags123Api(unittest.TestCase):
     """FakeClassnameTags123Api unit test stubs"""
 
     def setUp(self):
-        self.api = petstore_api.api.fake_classname_tags_123_api.FakeClassnameTags123Api()  # noqa: E501
+        self.api = FakeClassnameTags123Api()  # noqa: E501
 
     def tearDown(self):
         pass
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_file.py b/samples/openapi3/client/petstore/python-experimental/test/test_file.py
index af185e32e6e8..8d60f64e01cc 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_file.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_file.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.file import File
 
 
 class TestFile(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testFile(self):
         """Test File"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.File()  # noqa: E501
+        # model = File()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_file_schema_test_class.py b/samples/openapi3/client/petstore/python-experimental/test/test_file_schema_test_class.py
index c2de4e866cda..9a4f6d38dfef 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_file_schema_test_class.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_file_schema_test_class.py
@@ -11,10 +11,16 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import file
+except ImportError:
+    file = sys.modules[
+        'petstore_api.model.file']
+from petstore_api.model.file_schema_test_class import FileSchemaTestClass
 
 
 class TestFileSchemaTestClass(unittest.TestCase):
@@ -29,7 +35,7 @@ def tearDown(self):
     def testFileSchemaTestClass(self):
         """Test FileSchemaTestClass"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.FileSchemaTestClass()  # noqa: E501
+        # model = FileSchemaTestClass()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_foo.py b/samples/openapi3/client/petstore/python-experimental/test/test_foo.py
index c54feb98c25a..8125de84ada3 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_foo.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_foo.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.foo import Foo
 
 
 class TestFoo(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testFoo(self):
         """Test Foo"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Foo()  # noqa: E501
+        # model = Foo()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_format_test.py b/samples/openapi3/client/petstore/python-experimental/test/test_format_test.py
index a9d39521e934..07f4f5e4c1f7 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_format_test.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_format_test.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.format_test import FormatTest
 
 
 class TestFormatTest(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testFormatTest(self):
         """Test FormatTest"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.FormatTest()  # noqa: E501
+        # model = FormatTest()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_fruit.py b/samples/openapi3/client/petstore/python-experimental/test/test_fruit.py
index 1172373b9e1d..1eb9d09d5061 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_fruit.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_fruit.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import apple
+except ImportError:
+    apple = sys.modules[
+        'petstore_api.model.apple']
+try:
+    from petstore_api.model import banana
+except ImportError:
+    banana = sys.modules[
+        'petstore_api.model.banana']
+from petstore_api.model.fruit import Fruit
 
 
 class TestFruit(unittest.TestCase):
@@ -33,7 +44,7 @@ def testFruit(self):
         # banana test
         length_cm = 20.3
         color = 'yellow'
-        fruit = petstore_api.Fruit(length_cm=length_cm, color=color)
+        fruit = Fruit(length_cm=length_cm, color=color)
         # check its properties
         self.assertEqual(fruit.length_cm, length_cm)
         self.assertEqual(fruit['length_cm'], length_cm)
@@ -79,7 +90,7 @@ def testFruit(self):
         # Per Python doc, if the named attribute does not exist,
         # default is returned if provided, otherwise AttributeError is raised.
         with self.assertRaises(AttributeError):
-          getattr(fruit, 'cultivar')
+            getattr(fruit, 'cultivar')
 
         # make sure that the ModelComposed class properties are correct
         # model._composed_schemas stores the anyOf/allOf/oneOf info
@@ -89,15 +100,15 @@ def testFruit(self):
                 'anyOf': [],
                 'allOf': [],
                 'oneOf': [
-                    petstore_api.Apple,
-                    petstore_api.Banana,
+                    apple.Apple,
+                    banana.Banana,
                 ],
             }
         )
         # model._composed_instances is a list of the instances that were
         # made from the anyOf/allOf/OneOf classes in model._composed_schemas
         for composed_instance in fruit._composed_instances:
-            if composed_instance.__class__ == petstore_api.Banana:
+            if composed_instance.__class__ == banana.Banana:
                 banana_instance = composed_instance
         self.assertEqual(
             fruit._composed_instances,
@@ -129,7 +140,7 @@ def testFruit(self):
 
         # including extra parameters raises an exception
         with self.assertRaises(petstore_api.ApiValueError):
-            fruit = petstore_api.Fruit(
+            fruit = Fruit(
                 color=color,
                 length_cm=length_cm,
                 unknown_property='some value'
@@ -137,7 +148,7 @@ def testFruit(self):
 
         # including input parameters for two oneOf instances raise an exception
         with self.assertRaises(petstore_api.ApiValueError):
-            fruit = petstore_api.Fruit(
+            fruit = Fruit(
                 length_cm=length_cm,
                 cultivar='granny smith'
             )
@@ -146,7 +157,7 @@ def testFruit(self):
         # apple test
         color = 'red'
         cultivar = 'golden delicious'
-        fruit = petstore_api.Fruit(color=color, cultivar=cultivar)
+        fruit = Fruit(color=color, cultivar=cultivar)
         # check its properties
         self.assertEqual(fruit.color, color)
         self.assertEqual(fruit['color'], color)
@@ -166,7 +177,7 @@ def testFruit(self):
         # model._composed_instances is a list of the instances that were
         # made from the anyOf/allOf/OneOf classes in model._composed_schemas
         for composed_instance in fruit._composed_instances:
-            if composed_instance.__class__ == petstore_api.Apple:
+            if composed_instance.__class__ == apple.Apple:
                 apple_instance = composed_instance
         self.assertEqual(
             fruit._composed_instances,
@@ -191,20 +202,20 @@ def testFruit(self):
 
     def testFruitNullValue(self):
         # Since 'apple' is nullable, validate we can create an apple with the 'null' value.
-        apple = petstore_api.Apple(None)
-        self.assertIsNone(apple)
+        fruit = apple.Apple(None)
+        self.assertIsNone(fruit)
 
         # 'banana' is not nullable.
         with self.assertRaises(petstore_api.ApiTypeError):
-            banana = petstore_api.Banana(None)
+            banana.Banana(None)
 
         # Since 'fruit' has oneOf 'apple', 'banana' and 'apple' is nullable,
         # validate we can create a fruit with the 'null' value.
-        fruit = petstore_api.Fruit(None)
+        fruit = Fruit(None)
         self.assertIsNone(fruit)
  
         # Redo the same thing, this time passing a null Apple to the Fruit constructor.
-        fruit = petstore_api.Fruit(petstore_api.Apple(None))
+        fruit = Fruit(apple.Apple(None))
         self.assertIsNone(fruit)
 
 if __name__ == '__main__':
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_fruit_req.py b/samples/openapi3/client/petstore/python-experimental/test/test_fruit_req.py
index f3e03faf271c..3a1aa8fc283b 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_fruit_req.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_fruit_req.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import apple_req
+except ImportError:
+    apple_req = sys.modules[
+        'petstore_api.model.apple_req']
+try:
+    from petstore_api.model import banana_req
+except ImportError:
+    banana_req = sys.modules[
+        'petstore_api.model.banana_req']
+from petstore_api.model.fruit_req import FruitReq
 
 
 class TestFruitReq(unittest.TestCase):
@@ -32,7 +43,7 @@ def testFruitReq(self):
         # make an instance of Fruit, a composed schema oneOf model
         # banana test
         length_cm = 20.3
-        fruit = petstore_api.FruitReq(length_cm=length_cm)
+        fruit = FruitReq(length_cm=length_cm)
         # check its properties
         self.assertEqual(fruit.length_cm, length_cm)
         self.assertEqual(fruit['length_cm'], length_cm)
@@ -70,8 +81,8 @@ def testFruitReq(self):
                 'anyOf': [],
                 'allOf': [],
                 'oneOf': [
-                    petstore_api.AppleReq,
-                    petstore_api.BananaReq,
+                    apple_req.AppleReq,
+                    banana_req.BananaReq,
                     type(None),
                 ],
             }
@@ -79,7 +90,7 @@ def testFruitReq(self):
         # model._composed_instances is a list of the instances that were
         # made from the anyOf/allOf/OneOf classes in model._composed_schemas
         for composed_instance in fruit._composed_instances:
-            if composed_instance.__class__ == petstore_api.BananaReq:
+            if composed_instance.__class__ == banana_req.BananaReq:
                 banana_instance = composed_instance
         self.assertEqual(
             fruit._composed_instances,
@@ -111,14 +122,14 @@ def testFruitReq(self):
 
         # including extra parameters raises an exception
         with self.assertRaises(petstore_api.ApiValueError):
-            fruit = petstore_api.FruitReq(
+            fruit = FruitReq(
                 length_cm=length_cm,
                 unknown_property='some value'
             )
 
         # including input parameters for two oneOf instances raise an exception
         with self.assertRaises(petstore_api.ApiValueError):
-            fruit = petstore_api.FruitReq(
+            fruit = FruitReq(
                 length_cm=length_cm,
                 cultivar='granny smith'
             )
@@ -126,7 +137,7 @@ def testFruitReq(self):
         # make an instance of Fruit, a composed schema oneOf model
         # apple test
         cultivar = 'golden delicious'
-        fruit = petstore_api.FruitReq(cultivar=cultivar)
+        fruit = FruitReq(cultivar=cultivar)
         # check its properties
         self.assertEqual(fruit.cultivar, cultivar)
         self.assertEqual(fruit['cultivar'], cultivar)
@@ -142,7 +153,7 @@ def testFruitReq(self):
         # model._composed_instances is a list of the instances that were
         # made from the anyOf/allOf/OneOf classes in model._composed_schemas
         for composed_instance in fruit._composed_instances:
-            if composed_instance.__class__ == petstore_api.AppleReq:
+            if composed_instance.__class__ == apple_req.AppleReq:
                 apple_instance = composed_instance
         self.assertEqual(
             fruit._composed_instances,
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_gm_fruit.py b/samples/openapi3/client/petstore/python-experimental/test/test_gm_fruit.py
index c68121f1fd8f..9d13e90659d0 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_gm_fruit.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_gm_fruit.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import apple
+except ImportError:
+    apple = sys.modules[
+        'petstore_api.model.apple']
+try:
+    from petstore_api.model import banana
+except ImportError:
+    banana = sys.modules[
+        'petstore_api.model.banana']
+from petstore_api.model.gm_fruit import GmFruit
 
 
 class TestGmFruit(unittest.TestCase):
@@ -33,7 +44,7 @@ def testGmFruit(self):
         # banana test
         length_cm = 20.3
         color = 'yellow'
-        fruit = petstore_api.GmFruit(length_cm=length_cm, color=color)
+        fruit = GmFruit(length_cm=length_cm, color=color)
         # check its properties
         self.assertEqual(fruit.length_cm, length_cm)
         self.assertEqual(fruit['length_cm'], length_cm)
@@ -73,8 +84,8 @@ def testGmFruit(self):
             fruit._composed_schemas,
             {
                 'anyOf': [
-                    petstore_api.Apple,
-                    petstore_api.Banana,
+                    apple.Apple,
+                    banana.Banana,
                 ],
                 'allOf': [],
                 'oneOf': [],
@@ -83,7 +94,7 @@ def testGmFruit(self):
         # model._composed_instances is a list of the instances that were
         # made from the anyOf/allOf/OneOf classes in model._composed_schemas
         for composed_instance in fruit._composed_instances:
-            if composed_instance.__class__ == petstore_api.Banana:
+            if composed_instance.__class__ == banana.Banana:
                 banana_instance = composed_instance
         self.assertEqual(
             fruit._composed_instances,
@@ -115,7 +126,7 @@ def testGmFruit(self):
 
         # including extra parameters raises an exception
         with self.assertRaises(petstore_api.ApiValueError):
-            fruit = petstore_api.GmFruit(
+            fruit = GmFruit(
                 color=color,
                 length_cm=length_cm,
                 unknown_property='some value'
@@ -124,7 +135,7 @@ def testGmFruit(self):
         # including input parameters for both anyOf instances works
         cultivar = 'banaple'
         color = 'orange'
-        fruit = petstore_api.GmFruit(
+        fruit = GmFruit(
             color=color,
             cultivar=cultivar,
             length_cm=length_cm
@@ -142,9 +153,9 @@ def testGmFruit(self):
         # model._composed_instances is a list of the instances that were
         # made from the anyOf/allOf/OneOf classes in model._composed_schemas
         for composed_instance in fruit._composed_instances:
-            if composed_instance.__class__ == petstore_api.Apple:
+            if composed_instance.__class__ == apple.Apple:
                 apple_instance = composed_instance
-            elif composed_instance.__class__ == petstore_api.Banana:
+            elif composed_instance.__class__ == banana.Banana:
                 banana_instance = composed_instance
         self.assertEqual(
             fruit._composed_instances,
@@ -167,7 +178,7 @@ def testGmFruit(self):
         color = 'red'
         cultivar = 'golden delicious'
         origin = 'California'
-        fruit = petstore_api.GmFruit(color=color, cultivar=cultivar, origin=origin)
+        fruit = GmFruit(color=color, cultivar=cultivar, origin=origin)
         # check its properties
         self.assertEqual(fruit.color, color)
         self.assertEqual(fruit['color'], color)
@@ -193,7 +204,7 @@ def testGmFruit(self):
         # model._composed_instances is a list of the instances that were
         # made from the anyOf/allOf/OneOf classes in model._composed_schemas
         for composed_instance in fruit._composed_instances:
-            if composed_instance.__class__ == petstore_api.Apple:
+            if composed_instance.__class__ == apple.Apple:
                 apple_instance = composed_instance
         self.assertEqual(
             fruit._composed_instances,
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_grandparent_animal.py b/samples/openapi3/client/petstore/python-experimental/test/test_grandparent_animal.py
index dc0d300cdaea..286ef176575b 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_grandparent_animal.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_grandparent_animal.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import child_cat
+except ImportError:
+    child_cat = sys.modules[
+        'petstore_api.model.child_cat']
+try:
+    from petstore_api.model import parent_pet
+except ImportError:
+    parent_pet = sys.modules[
+        'petstore_api.model.parent_pet']
+from petstore_api.model.grandparent_animal import GrandparentAnimal
 
 
 class TestGrandparentAnimal(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testGrandparentAnimal(self):
         """Test GrandparentAnimal"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.GrandparentAnimal()  # noqa: E501
+        # model = GrandparentAnimal()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_has_only_read_only.py b/samples/openapi3/client/petstore/python-experimental/test/test_has_only_read_only.py
index e042faf7c94c..9ebd7683b398 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_has_only_read_only.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_has_only_read_only.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.has_only_read_only import HasOnlyReadOnly
 
 
 class TestHasOnlyReadOnly(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testHasOnlyReadOnly(self):
         """Test HasOnlyReadOnly"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.HasOnlyReadOnly()  # noqa: E501
+        # model = HasOnlyReadOnly()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_health_check_result.py b/samples/openapi3/client/petstore/python-experimental/test/test_health_check_result.py
index ebcc32f43964..11ff5f5cf636 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_health_check_result.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_health_check_result.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.health_check_result import HealthCheckResult
 
 
 class TestHealthCheckResult(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testHealthCheckResult(self):
         """Test HealthCheckResult"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.HealthCheckResult()  # noqa: E501
+        # model = HealthCheckResult()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_inline_object.py b/samples/openapi3/client/petstore/python-experimental/test/test_inline_object.py
index fc2e177006a2..3b3eee80807c 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_inline_object.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_inline_object.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.inline_object import InlineObject
 
 
 class TestInlineObject(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testInlineObject(self):
         """Test InlineObject"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.InlineObject()  # noqa: E501
+        # model = InlineObject()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_inline_object1.py b/samples/openapi3/client/petstore/python-experimental/test/test_inline_object1.py
index 12a62225defd..77d4b46553dd 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_inline_object1.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_inline_object1.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.inline_object1 import InlineObject1
 
 
 class TestInlineObject1(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testInlineObject1(self):
         """Test InlineObject1"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.InlineObject1()  # noqa: E501
+        # model = InlineObject1()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_inline_object2.py b/samples/openapi3/client/petstore/python-experimental/test/test_inline_object2.py
index 1651197f964b..b2310f152179 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_inline_object2.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_inline_object2.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.inline_object2 import InlineObject2
 
 
 class TestInlineObject2(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testInlineObject2(self):
         """Test InlineObject2"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.InlineObject2()  # noqa: E501
+        # model = InlineObject2()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_inline_object3.py b/samples/openapi3/client/petstore/python-experimental/test/test_inline_object3.py
index 2efbae377dde..afe7ca434286 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_inline_object3.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_inline_object3.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.inline_object3 import InlineObject3
 
 
 class TestInlineObject3(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testInlineObject3(self):
         """Test InlineObject3"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.InlineObject3()  # noqa: E501
+        # model = InlineObject3()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_inline_object4.py b/samples/openapi3/client/petstore/python-experimental/test/test_inline_object4.py
index 4f74d9cacacf..1b9bea4716dc 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_inline_object4.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_inline_object4.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.inline_object4 import InlineObject4
 
 
 class TestInlineObject4(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testInlineObject4(self):
         """Test InlineObject4"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.InlineObject4()  # noqa: E501
+        # model = InlineObject4()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_inline_object5.py b/samples/openapi3/client/petstore/python-experimental/test/test_inline_object5.py
index 895cc44ea290..ac72c53c1e3c 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_inline_object5.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_inline_object5.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.inline_object5 import InlineObject5
 
 
 class TestInlineObject5(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testInlineObject5(self):
         """Test InlineObject5"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.InlineObject5()  # noqa: E501
+        # model = InlineObject5()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_inline_response_default.py b/samples/openapi3/client/petstore/python-experimental/test/test_inline_response_default.py
index ecdd05f72fa4..b52167aea166 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_inline_response_default.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_inline_response_default.py
@@ -11,10 +11,16 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import foo
+except ImportError:
+    foo = sys.modules[
+        'petstore_api.model.foo']
+from petstore_api.model.inline_response_default import InlineResponseDefault
 
 
 class TestInlineResponseDefault(unittest.TestCase):
@@ -29,7 +35,7 @@ def tearDown(self):
     def testInlineResponseDefault(self):
         """Test InlineResponseDefault"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.InlineResponseDefault()  # noqa: E501
+        # model = InlineResponseDefault()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_isosceles_triangle.py b/samples/openapi3/client/petstore/python-experimental/test/test_isosceles_triangle.py
index 1f27f751d061..d89ae6ab78dd 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_isosceles_triangle.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_isosceles_triangle.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import shape_interface
+except ImportError:
+    shape_interface = sys.modules[
+        'petstore_api.model.shape_interface']
+try:
+    from petstore_api.model import triangle_interface
+except ImportError:
+    triangle_interface = sys.modules[
+        'petstore_api.model.triangle_interface']
+from petstore_api.model.isosceles_triangle import IsoscelesTriangle
 
 
 class TestIsoscelesTriangle(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testIsoscelesTriangle(self):
         """Test IsoscelesTriangle"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.IsoscelesTriangle()  # noqa: E501
+        # model = IsoscelesTriangle()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_list.py b/samples/openapi3/client/petstore/python-experimental/test/test_list.py
index 29979911a8e9..52156adfed2e 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_list.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_list.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.list import List
 
 
 class TestList(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testList(self):
         """Test List"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.List()  # noqa: E501
+        # model = List()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_mammal.py b/samples/openapi3/client/petstore/python-experimental/test/test_mammal.py
index cc783f53ed64..2a8893d02fb3 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_mammal.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_mammal.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import whale
+except ImportError:
+    whale = sys.modules[
+        'petstore_api.model.whale']
+try:
+    from petstore_api.model import zebra
+except ImportError:
+    zebra = sys.modules[
+        'petstore_api.model.zebra']
+from petstore_api.model.mammal import Mammal
 
 
 class TestMammal(unittest.TestCase):
@@ -30,8 +41,9 @@ def testMammal(self):
         """Test Mammal"""
 
         # tests that we can make a BasquePig by traveling through descendant discriminator in Pig
-        model = petstore_api.Mammal(class_name="BasquePig")
-        assert isinstance(model, petstore_api.BasquePig)
+        model = Mammal(class_name="BasquePig")
+        from petstore_api.model import basque_pig
+        assert isinstance(model, basque_pig.BasquePig)
 
 
 if __name__ == '__main__':
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_map_test.py b/samples/openapi3/client/petstore/python-experimental/test/test_map_test.py
index 8592f21949bd..88b28ff93dac 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_map_test.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_map_test.py
@@ -11,10 +11,16 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import string_boolean_map
+except ImportError:
+    string_boolean_map = sys.modules[
+        'petstore_api.model.string_boolean_map']
+from petstore_api.model.map_test import MapTest
 
 
 class TestMapTest(unittest.TestCase):
@@ -29,7 +35,7 @@ def tearDown(self):
     def testMapTest(self):
         """Test MapTest"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.MapTest()  # noqa: E501
+        # model = MapTest()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_mixed_properties_and_additional_properties_class.py b/samples/openapi3/client/petstore/python-experimental/test/test_mixed_properties_and_additional_properties_class.py
index a4e89d3e8c07..4dcb5ad4268c 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_mixed_properties_and_additional_properties_class.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_mixed_properties_and_additional_properties_class.py
@@ -11,10 +11,16 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import animal
+except ImportError:
+    animal = sys.modules[
+        'petstore_api.model.animal']
+from petstore_api.model.mixed_properties_and_additional_properties_class import MixedPropertiesAndAdditionalPropertiesClass
 
 
 class TestMixedPropertiesAndAdditionalPropertiesClass(unittest.TestCase):
@@ -29,7 +35,7 @@ def tearDown(self):
     def testMixedPropertiesAndAdditionalPropertiesClass(self):
         """Test MixedPropertiesAndAdditionalPropertiesClass"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.MixedPropertiesAndAdditionalPropertiesClass()  # noqa: E501
+        # model = MixedPropertiesAndAdditionalPropertiesClass()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_model200_response.py b/samples/openapi3/client/petstore/python-experimental/test/test_model200_response.py
index 149629fe1e8e..4012eaae3362 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_model200_response.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_model200_response.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.model200_response import Model200Response
 
 
 class TestModel200Response(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testModel200Response(self):
         """Test Model200Response"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Model200Response()  # noqa: E501
+        # model = Model200Response()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_model_return.py b/samples/openapi3/client/petstore/python-experimental/test/test_model_return.py
index e48b2c479839..54c98b33cd66 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_model_return.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_model_return.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.model_return import ModelReturn
 
 
 class TestModelReturn(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testModelReturn(self):
         """Test ModelReturn"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ModelReturn()  # noqa: E501
+        # model = ModelReturn()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_name.py b/samples/openapi3/client/petstore/python-experimental/test/test_name.py
index 1f6407683b29..6a9be99d1a57 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_name.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_name.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.name import Name
 
 
 class TestName(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testName(self):
         """Test Name"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Name()  # noqa: E501
+        # model = Name()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_nullable_class.py b/samples/openapi3/client/petstore/python-experimental/test/test_nullable_class.py
index 8af2cb8447ee..f73dc3d98bbb 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_nullable_class.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_nullable_class.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.nullable_class import NullableClass
 
 
 class TestNullableClass(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testNullableClass(self):
         """Test NullableClass"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.NullableClass()  # noqa: E501
+        # model = NullableClass()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_nullable_shape.py b/samples/openapi3/client/petstore/python-experimental/test/test_nullable_shape.py
index 1e22479d4db4..d6bf001743bf 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_nullable_shape.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_nullable_shape.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import quadrilateral
+except ImportError:
+    quadrilateral = sys.modules[
+        'petstore_api.model.quadrilateral']
+try:
+    from petstore_api.model import triangle
+except ImportError:
+    triangle = sys.modules[
+        'petstore_api.model.triangle']
+from petstore_api.model.nullable_shape import NullableShape
 
 
 class TestNullableShape(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testNullableShape(self):
         """Test NullableShape"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.NullableShape()  # noqa: E501
+        # model = NullableShape()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_number_only.py b/samples/openapi3/client/petstore/python-experimental/test/test_number_only.py
index 732baf4b84ed..07aab1d78af7 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_number_only.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_number_only.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.number_only import NumberOnly
 
 
 class TestNumberOnly(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testNumberOnly(self):
         """Test NumberOnly"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.NumberOnly()  # noqa: E501
+        # model = NumberOnly()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_order.py b/samples/openapi3/client/petstore/python-experimental/test/test_order.py
index 10ce38e954ea..604c67042c34 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_order.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_order.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.order import Order
 
 
 class TestOrder(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testOrder(self):
         """Test Order"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Order()  # noqa: E501
+        # model = Order()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_outer_composite.py b/samples/openapi3/client/petstore/python-experimental/test/test_outer_composite.py
index c191d04ec6b2..7da5c1f09b59 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_outer_composite.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_outer_composite.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.outer_composite import OuterComposite
 
 
 class TestOuterComposite(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testOuterComposite(self):
         """Test OuterComposite"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.OuterComposite()  # noqa: E501
+        # model = OuterComposite()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum.py b/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum.py
index fbb8cb7ad5cf..ab9dac9d612b 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.outer_enum import OuterEnum
 
 
 class TestOuterEnum(unittest.TestCase):
@@ -30,15 +31,14 @@ def testOuterEnum(self):
         """Test OuterEnum"""
         # Since 'OuterEnum' is nullable, validate the null value can be assigned
         # to OuterEnum.
-        inst = petstore_api.OuterEnum(None)
+        inst = OuterEnum(None)
         self.assertIsNone(inst)
 
-        inst = petstore_api.OuterEnum('approved')
-        assert isinstance(inst, petstore_api.OuterEnum)
+        inst = OuterEnum('approved')
+        assert isinstance(inst, OuterEnum)
 
         with self.assertRaises(petstore_api.ApiValueError):
-            inst = petstore_api.OuterEnum('garbage')
-            assert isinstance(inst, petstore_api.OuterEnum)
+            OuterEnum('garbage')
 
 
 if __name__ == '__main__':
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum_default_value.py b/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum_default_value.py
index 80c9534a88e2..a0f6fb3cef51 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum_default_value.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum_default_value.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.outer_enum_default_value import OuterEnumDefaultValue
 
 
 class TestOuterEnumDefaultValue(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testOuterEnumDefaultValue(self):
         """Test OuterEnumDefaultValue"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.OuterEnumDefaultValue()  # noqa: E501
+        # model = OuterEnumDefaultValue()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum_integer.py b/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum_integer.py
index 60724eefd711..9e0fa2975b4b 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum_integer.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum_integer.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.outer_enum_integer import OuterEnumInteger
 
 
 class TestOuterEnumInteger(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testOuterEnumInteger(self):
         """Test OuterEnumInteger"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.OuterEnumInteger()  # noqa: E501
+        # model = OuterEnumInteger()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum_integer_default_value.py b/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum_integer_default_value.py
index 8eca8fa69ac1..6eb78f95b0cf 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum_integer_default_value.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_outer_enum_integer_default_value.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.outer_enum_integer_default_value import OuterEnumIntegerDefaultValue
 
 
 class TestOuterEnumIntegerDefaultValue(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testOuterEnumIntegerDefaultValue(self):
         """Test OuterEnumIntegerDefaultValue"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.OuterEnumIntegerDefaultValue()  # noqa: E501
+        # model = OuterEnumIntegerDefaultValue()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_parent_pet.py b/samples/openapi3/client/petstore/python-experimental/test/test_parent_pet.py
index 8db04124d66e..15262872e195 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_parent_pet.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_parent_pet.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import child_cat
+except ImportError:
+    child_cat = sys.modules[
+        'petstore_api.model.child_cat']
+try:
+    from petstore_api.model import grandparent_animal
+except ImportError:
+    grandparent_animal = sys.modules[
+        'petstore_api.model.grandparent_animal']
+from petstore_api.model.parent_pet import ParentPet
 
 
 class TestParentPet(unittest.TestCase):
@@ -32,8 +43,9 @@ def testParentPet(self):
         # test that we can make a ParentPet from a ParentPet
         # which requires that we travel back through ParentPet's allOf descendant
         # GrandparentAnimal, and we use the descendant's discriminator to make ParentPet
-        model = petstore_api.ParentPet(pet_type="ParentPet")
-        assert isinstance(model, petstore_api.ParentPet)
+        model = ParentPet(pet_type="ParentPet")
+        assert isinstance(model, ParentPet)
+
 
 if __name__ == '__main__':
     unittest.main()
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_pet.py b/samples/openapi3/client/petstore/python-experimental/test/test_pet.py
index db9e3729f505..fb8586e4090c 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_pet.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_pet.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import category
+except ImportError:
+    category = sys.modules[
+        'petstore_api.model.category']
+try:
+    from petstore_api.model import tag
+except ImportError:
+    tag = sys.modules[
+        'petstore_api.model.tag']
+from petstore_api.model.pet import Pet
 
 
 class TestPet(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testPet(self):
         """Test Pet"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Pet()  # noqa: E501
+        # model = Pet()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_pet_api.py b/samples/openapi3/client/petstore/python-experimental/test/test_pet_api.py
index 77665df879f1..3f2d3a8847ca 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_pet_api.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_pet_api.py
@@ -16,14 +16,13 @@
 
 import petstore_api
 from petstore_api.api.pet_api import PetApi  # noqa: E501
-from petstore_api.rest import ApiException
 
 
 class TestPetApi(unittest.TestCase):
     """PetApi unit test stubs"""
 
     def setUp(self):
-        self.api = petstore_api.api.pet_api.PetApi()  # noqa: E501
+        self.api = PetApi()  # noqa: E501
 
     def tearDown(self):
         pass
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_pig.py b/samples/openapi3/client/petstore/python-experimental/test/test_pig.py
index afdd210da7d9..f98bed3f1910 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_pig.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_pig.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import basque_pig
+except ImportError:
+    basque_pig = sys.modules[
+        'petstore_api.model.basque_pig']
+try:
+    from petstore_api.model import danish_pig
+except ImportError:
+    danish_pig = sys.modules[
+        'petstore_api.model.danish_pig']
+from petstore_api.model.pig import Pig
 
 
 class TestPig(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testPig(self):
         """Test Pig"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Pig()  # noqa: E501
+        # model = Pig()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_quadrilateral.py b/samples/openapi3/client/petstore/python-experimental/test/test_quadrilateral.py
index 9bb838811892..149b9a0070b6 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_quadrilateral.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_quadrilateral.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import complex_quadrilateral
+except ImportError:
+    complex_quadrilateral = sys.modules[
+        'petstore_api.model.complex_quadrilateral']
+try:
+    from petstore_api.model import simple_quadrilateral
+except ImportError:
+    simple_quadrilateral = sys.modules[
+        'petstore_api.model.simple_quadrilateral']
+from petstore_api.model.quadrilateral import Quadrilateral
 
 
 class TestQuadrilateral(unittest.TestCase):
@@ -28,10 +39,10 @@ def tearDown(self):
 
     def testQuadrilateral(self):
         """Test Quadrilateral"""
-        complex_quadrilateral = petstore_api.Quadrilateral(shape_type="Quadrilateral", quadrilateral_type="ComplexQuadrilateral")
-        assert isinstance(complex_quadrilateral, petstore_api.ComplexQuadrilateral)
-        simple_quadrilateral = petstore_api.Quadrilateral(shape_type="Quadrilateral", quadrilateral_type="SimpleQuadrilateral")
-        assert isinstance(simple_quadrilateral, petstore_api.SimpleQuadrilateral)
+        instance = Quadrilateral(shape_type="Quadrilateral", quadrilateral_type="ComplexQuadrilateral")
+        assert isinstance(instance, complex_quadrilateral.ComplexQuadrilateral)
+        instance = Quadrilateral(shape_type="Quadrilateral", quadrilateral_type="SimpleQuadrilateral")
+        assert isinstance(instance, simple_quadrilateral.SimpleQuadrilateral)
 
 
 if __name__ == '__main__':
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_quadrilateral_interface.py b/samples/openapi3/client/petstore/python-experimental/test/test_quadrilateral_interface.py
index 7a48ce64a9df..0b2e32dc37af 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_quadrilateral_interface.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_quadrilateral_interface.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.quadrilateral_interface import QuadrilateralInterface
 
 
 class TestQuadrilateralInterface(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testQuadrilateralInterface(self):
         """Test QuadrilateralInterface"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.QuadrilateralInterface()  # noqa: E501
+        # model = QuadrilateralInterface()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_read_only_first.py b/samples/openapi3/client/petstore/python-experimental/test/test_read_only_first.py
index 553768f3303a..c2dcde240e77 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_read_only_first.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_read_only_first.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.read_only_first import ReadOnlyFirst
 
 
 class TestReadOnlyFirst(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testReadOnlyFirst(self):
         """Test ReadOnlyFirst"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ReadOnlyFirst()  # noqa: E501
+        # model = ReadOnlyFirst()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_scalene_triangle.py b/samples/openapi3/client/petstore/python-experimental/test/test_scalene_triangle.py
index 8452fc183137..f5f1ccb3efa0 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_scalene_triangle.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_scalene_triangle.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import shape_interface
+except ImportError:
+    shape_interface = sys.modules[
+        'petstore_api.model.shape_interface']
+try:
+    from petstore_api.model import triangle_interface
+except ImportError:
+    triangle_interface = sys.modules[
+        'petstore_api.model.triangle_interface']
+from petstore_api.model.scalene_triangle import ScaleneTriangle
 
 
 class TestScaleneTriangle(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testScaleneTriangle(self):
         """Test ScaleneTriangle"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ScaleneTriangle()  # noqa: E501
+        # model = ScaleneTriangle()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_shape.py b/samples/openapi3/client/petstore/python-experimental/test/test_shape.py
index e06fd0cb6faf..4424679aeccb 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_shape.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_shape.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import quadrilateral
+except ImportError:
+    quadrilateral = sys.modules[
+        'petstore_api.model.quadrilateral']
+try:
+    from petstore_api.model import triangle
+except ImportError:
+    triangle = sys.modules[
+        'petstore_api.model.triangle']
+from petstore_api.model.shape import Shape
 
 
 class TestShape(unittest.TestCase):
@@ -28,67 +39,71 @@ def tearDown(self):
 
     def testShape(self):
         """Test Shape"""
-        equilateral_triangle = petstore_api.Triangle(
+        from petstore_api.model import complex_quadrilateral
+        from petstore_api.model import simple_quadrilateral
+        from petstore_api.model import equilateral_triangle
+        from petstore_api.model import isosceles_triangle
+        from petstore_api.model import scalene_triangle
+        tri = triangle.Triangle(
             shape_type="Triangle",
             triangle_type="EquilateralTriangle"
         )
-        assert isinstance(equilateral_triangle, petstore_api.EquilateralTriangle)
+        assert isinstance(tri, equilateral_triangle.EquilateralTriangle)
 
-        isosceles_triangle = petstore_api.Triangle(
+        tri = triangle.Triangle(
             shape_type="Triangle",
             triangle_type="IsoscelesTriangle"
         )
-        assert isinstance(isosceles_triangle, petstore_api.IsoscelesTriangle)
+        assert isinstance(tri, isosceles_triangle.IsoscelesTriangle)
 
-        scalene_triangle = petstore_api.Triangle(
+        tri = triangle.Triangle(
             shape_type="Triangle",
             triangle_type="ScaleneTriangle"
         )
-        assert isinstance(scalene_triangle, petstore_api.ScaleneTriangle)
+        assert isinstance(tri, scalene_triangle.ScaleneTriangle)
 
-        complex_quadrilateral = petstore_api.Shape(
+        quad = Shape(
             shape_type="Quadrilateral",
             quadrilateral_type="ComplexQuadrilateral"
         )
-        assert isinstance(complex_quadrilateral, petstore_api.ComplexQuadrilateral)
+        assert isinstance(quad, complex_quadrilateral.ComplexQuadrilateral)
 
-        simple_quadrilateral = petstore_api.Shape(
+        quad = Shape(
             shape_type="Quadrilateral",
             quadrilateral_type="SimpleQuadrilateral"
         )
-        assert isinstance(simple_quadrilateral, petstore_api.SimpleQuadrilateral)
+        assert isinstance(quad, simple_quadrilateral.SimpleQuadrilateral)
 
         # No discriminator provided.
         err_msg = ("Cannot deserialize input data due to missing discriminator. "
-                "The discriminator property '{}' is missing at path: ()"
-        )
+                   "The discriminator property '{}' is missing at path: ()"
+                   )
         with self.assertRaisesRegexp(
-            petstore_api.ApiValueError,
-            err_msg.format("shapeType")
+                petstore_api.ApiValueError,
+                err_msg.format("shapeType")
         ):
-            petstore_api.Shape()
+            Shape()
 
         # invalid shape_type (first discriminator). 'Circle' does not exist in the model.
         err_msg = ("Cannot deserialize input data due to invalid discriminator "
-            "value. The OpenAPI document has no mapping for discriminator "
-            "property '{}'='{}' at path: ()"
-        )
+                   "value. The OpenAPI document has no mapping for discriminator "
+                   "property '{}'='{}' at path: ()"
+                   )
         with self.assertRaisesRegexp(
-            petstore_api.ApiValueError,
-            err_msg.format("shapeType", "Circle")
+                petstore_api.ApiValueError,
+                err_msg.format("shapeType", "Circle")
         ):
-            petstore_api.Shape(shape_type="Circle")
+            Shape(shape_type="Circle")
 
         # invalid quadrilateral_type (second discriminator)
         with self.assertRaisesRegexp(
-            petstore_api.ApiValueError,
-            err_msg.format("quadrilateralType", "Triangle")
+                petstore_api.ApiValueError,
+                err_msg.format("quadrilateralType", "Triangle")
         ):
-            petstore_api.Shape(
+            Shape(
                 shape_type="Quadrilateral",
                 quadrilateral_type="Triangle"
             )
 
-
 if __name__ == '__main__':
     unittest.main()
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_shape_interface.py b/samples/openapi3/client/petstore/python-experimental/test/test_shape_interface.py
index a768951489a0..c8b0270f9fc5 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_shape_interface.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_shape_interface.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.shape_interface import ShapeInterface
 
 
 class TestShapeInterface(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testShapeInterface(self):
         """Test ShapeInterface"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ShapeInterface()  # noqa: E501
+        # model = ShapeInterface()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_shape_or_null.py b/samples/openapi3/client/petstore/python-experimental/test/test_shape_or_null.py
index b04d847204bc..e3bfa41e7e84 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_shape_or_null.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_shape_or_null.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import quadrilateral
+except ImportError:
+    quadrilateral = sys.modules[
+        'petstore_api.model.quadrilateral']
+try:
+    from petstore_api.model import triangle
+except ImportError:
+    triangle = sys.modules[
+        'petstore_api.model.triangle']
+from petstore_api.model.shape_or_null import ShapeOrNull
 
 
 class TestShapeOrNull(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testShapeOrNull(self):
         """Test ShapeOrNull"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.ShapeOrNull()  # noqa: E501
+        # model = ShapeOrNull()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_simple_quadrilateral.py b/samples/openapi3/client/petstore/python-experimental/test/test_simple_quadrilateral.py
index f51722093445..b08ddf1c6781 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_simple_quadrilateral.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_simple_quadrilateral.py
@@ -11,10 +11,21 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import quadrilateral_interface
+except ImportError:
+    quadrilateral_interface = sys.modules[
+        'petstore_api.model.quadrilateral_interface']
+try:
+    from petstore_api.model import shape_interface
+except ImportError:
+    shape_interface = sys.modules[
+        'petstore_api.model.shape_interface']
+from petstore_api.model.simple_quadrilateral import SimpleQuadrilateral
 
 
 class TestSimpleQuadrilateral(unittest.TestCase):
@@ -29,7 +40,7 @@ def tearDown(self):
     def testSimpleQuadrilateral(self):
         """Test SimpleQuadrilateral"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.SimpleQuadrilateral()  # noqa: E501
+        # model = SimpleQuadrilateral()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_special_model_name.py b/samples/openapi3/client/petstore/python-experimental/test/test_special_model_name.py
index 7de520d9cefe..6124525f5170 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_special_model_name.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_special_model_name.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.special_model_name import SpecialModelName
 
 
 class TestSpecialModelName(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testSpecialModelName(self):
         """Test SpecialModelName"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.SpecialModelName()  # noqa: E501
+        # model = SpecialModelName()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_store_api.py b/samples/openapi3/client/petstore/python-experimental/test/test_store_api.py
index 81848d24a67e..0d9cc3dd36ea 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_store_api.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_store_api.py
@@ -16,14 +16,13 @@
 
 import petstore_api
 from petstore_api.api.store_api import StoreApi  # noqa: E501
-from petstore_api.rest import ApiException
 
 
 class TestStoreApi(unittest.TestCase):
     """StoreApi unit test stubs"""
 
     def setUp(self):
-        self.api = petstore_api.api.store_api.StoreApi()  # noqa: E501
+        self.api = StoreApi()  # noqa: E501
 
     def tearDown(self):
         pass
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_string_boolean_map.py b/samples/openapi3/client/petstore/python-experimental/test/test_string_boolean_map.py
index af071721eba3..e2e9d8b420b8 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_string_boolean_map.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_string_boolean_map.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.string_boolean_map import StringBooleanMap
 
 
 class TestStringBooleanMap(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testStringBooleanMap(self):
         """Test StringBooleanMap"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.StringBooleanMap()  # noqa: E501
+        # model = StringBooleanMap()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_tag.py b/samples/openapi3/client/petstore/python-experimental/test/test_tag.py
index 27c2be5391ab..b0a09d94a785 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_tag.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_tag.py
@@ -15,6 +15,7 @@
 import unittest
 
 import petstore_api
+from petstore_api.model.tag import Tag
 
 
 class TestTag(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testTag(self):
         """Test Tag"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Tag()  # noqa: E501
+        # model = Tag()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_triangle.py b/samples/openapi3/client/petstore/python-experimental/test/test_triangle.py
index 42037a1ec79b..65ae20743e14 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_triangle.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_triangle.py
@@ -11,10 +11,26 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+try:
+    from petstore_api.model import equilateral_triangle
+except ImportError:
+    equilateral_triangle = sys.modules[
+        'petstore_api.model.equilateral_triangle']
+try:
+    from petstore_api.model import isosceles_triangle
+except ImportError:
+    isosceles_triangle = sys.modules[
+        'petstore_api.model.isosceles_triangle']
+try:
+    from petstore_api.model import scalene_triangle
+except ImportError:
+    scalene_triangle = sys.modules[
+        'petstore_api.model.scalene_triangle']
+from petstore_api.model.triangle import Triangle
 
 
 class TestTriangle(unittest.TestCase):
@@ -28,12 +44,12 @@ def tearDown(self):
 
     def testTriangle(self):
         """Test Triangle"""
-        equilateral_triangle = petstore_api.Triangle(shape_type="Triangle", triangle_type="EquilateralTriangle")
-        assert isinstance(equilateral_triangle, petstore_api.EquilateralTriangle)
-        isosceles_triangle = petstore_api.Triangle(shape_type="Triangle", triangle_type="IsoscelesTriangle")
-        assert isinstance(isosceles_triangle, petstore_api.IsoscelesTriangle)
-        scalene_triangle = petstore_api.Triangle(shape_type="Triangle", triangle_type="ScaleneTriangle")
-        assert isinstance(scalene_triangle, petstore_api.ScaleneTriangle)
+        tri = Triangle(shape_type="Triangle", triangle_type="EquilateralTriangle")
+        assert isinstance(tri, equilateral_triangle.EquilateralTriangle)
+        tri = Triangle(shape_type="Triangle", triangle_type="IsoscelesTriangle")
+        assert isinstance(tri, isosceles_triangle.IsoscelesTriangle)
+        tri = Triangle(shape_type="Triangle", triangle_type="ScaleneTriangle")
+        assert isinstance(tri, scalene_triangle.ScaleneTriangle)
 
 
 if __name__ == '__main__':
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_triangle_interface.py b/samples/openapi3/client/petstore/python-experimental/test/test_triangle_interface.py
index 4d87e647e61e..e087651a7d55 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_triangle_interface.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_triangle_interface.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.triangle_interface import TriangleInterface
 
 
 class TestTriangleInterface(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testTriangleInterface(self):
         """Test TriangleInterface"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.TriangleInterface()  # noqa: E501
+        # model = TriangleInterface()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_user.py b/samples/openapi3/client/petstore/python-experimental/test/test_user.py
index 3df641e29b6a..7241bb589c52 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_user.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_user.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.user import User
 
 
 class TestUser(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testUser(self):
         """Test User"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.User()  # noqa: E501
+        # model = User()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_user_api.py b/samples/openapi3/client/petstore/python-experimental/test/test_user_api.py
index 6df730fba2b1..df306da07761 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_user_api.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_user_api.py
@@ -16,14 +16,13 @@
 
 import petstore_api
 from petstore_api.api.user_api import UserApi  # noqa: E501
-from petstore_api.rest import ApiException
 
 
 class TestUserApi(unittest.TestCase):
     """UserApi unit test stubs"""
 
     def setUp(self):
-        self.api = petstore_api.api.user_api.UserApi()  # noqa: E501
+        self.api = UserApi()  # noqa: E501
 
     def tearDown(self):
         pass
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_whale.py b/samples/openapi3/client/petstore/python-experimental/test/test_whale.py
index 35d68f0cda02..3ad793af3e43 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_whale.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_whale.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.whale import Whale
 
 
 class TestWhale(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testWhale(self):
         """Test Whale"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Whale()  # noqa: E501
+        # model = Whale()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/test/test_zebra.py b/samples/openapi3/client/petstore/python-experimental/test/test_zebra.py
index 6013bd9a9a20..fe3245cced48 100644
--- a/samples/openapi3/client/petstore/python-experimental/test/test_zebra.py
+++ b/samples/openapi3/client/petstore/python-experimental/test/test_zebra.py
@@ -11,10 +11,11 @@
 
 
 from __future__ import absolute_import
-
+import sys
 import unittest
 
 import petstore_api
+from petstore_api.model.zebra import Zebra
 
 
 class TestZebra(unittest.TestCase):
@@ -29,7 +30,7 @@ def tearDown(self):
     def testZebra(self):
         """Test Zebra"""
         # FIXME: construct object with mandatory attributes with example values
-        # model = petstore_api.Zebra()  # noqa: E501
+        # model = Zebra()  # noqa: E501
         pass
 
 
diff --git a/samples/openapi3/client/petstore/python-experimental/tests/test_api_validation.py b/samples/openapi3/client/petstore/python-experimental/tests/test_api_validation.py
index a8a7276142bc..edf48ad0160b 100644
--- a/samples/openapi3/client/petstore/python-experimental/tests/test_api_validation.py
+++ b/samples/openapi3/client/petstore/python-experimental/tests/test_api_validation.py
@@ -21,6 +21,7 @@
 from collections import namedtuple
 
 import petstore_api
+from petstore_api.model import format_test
 import petstore_api.configuration
 
 HOST = 'http://petstore.swagger.io/v2'
@@ -50,7 +51,7 @@ def checkRaiseRegex(self, expected_exception, expected_regex):
 
 
     def test_multiple_of(self):
-        inst = petstore_api.FormatTest(
+        inst = format_test.FormatTest(
             byte='3',
             date=datetime.date(2000, 1, 1),
             password="abcdefghijkl",
@@ -58,10 +59,10 @@ def test_multiple_of(self):
             number=65.0,
             float=62.4
         )
-        assert isinstance(inst, petstore_api.FormatTest)
+        assert isinstance(inst, format_test.FormatTest)
 
         with self.checkRaiseRegex(petstore_api.exceptions.ApiValueError, "Invalid value for `integer`, value must be a multiple of `2`"):
-          inst = petstore_api.FormatTest(
+          inst = format_test.FormatTest(
               byte='3',
               date=datetime.date(2000, 1, 1),
               password="abcdefghijkl",
@@ -80,8 +81,8 @@ def test_multiple_of_deserialization(self):
             'float': 62.4,
         }
         response = MockResponse(data=json.dumps(data))
-        deserialized = self.api_client.deserialize(response, (petstore_api.FormatTest,), True)
-        self.assertTrue(isinstance(deserialized, petstore_api.FormatTest))
+        deserialized = self.api_client.deserialize(response, (format_test.FormatTest,), True)
+        self.assertTrue(isinstance(deserialized, format_test.FormatTest))
 
         with self.checkRaiseRegex(petstore_api.exceptions.ApiValueError, "Invalid value for `integer`, value must be a multiple of `2`"):
           data = {
@@ -93,7 +94,7 @@ def test_multiple_of_deserialization(self):
               'float': 62.4,
           }
           response = MockResponse(data=json.dumps(data))
-          deserialized = self.api_client.deserialize(response, (petstore_api.FormatTest,), True)
+          deserialized = self.api_client.deserialize(response, (format_test.FormatTest,), True)
 
         # Disable JSON schema validation. No error should be raised during deserialization.
         config = petstore_api.Configuration()
@@ -109,8 +110,8 @@ def test_multiple_of_deserialization(self):
             'float': 62.4,
         }
         response = MockResponse(data=json.dumps(data))
-        deserialized = api_client.deserialize(response, (petstore_api.FormatTest,), True)
-        self.assertTrue(isinstance(deserialized, petstore_api.FormatTest))
+        deserialized = api_client.deserialize(response, (format_test.FormatTest,), True)
+        self.assertTrue(isinstance(deserialized, format_test.FormatTest))
 
         # Disable JSON schema validation but for a different keyword.
         # An error should be raised during deserialization.
@@ -128,4 +129,4 @@ def test_multiple_of_deserialization(self):
                 'float': 62.4,
             }
             response = MockResponse(data=json.dumps(data))
-            deserialized = api_client.deserialize(response, (petstore_api.FormatTest,), True)
+            deserialized = api_client.deserialize(response, (format_test.FormatTest,), True)
diff --git a/samples/openapi3/client/petstore/python-experimental/tests/test_deserialization.py b/samples/openapi3/client/petstore/python-experimental/tests/test_deserialization.py
index a34df3425672..23e597d9bf54 100644
--- a/samples/openapi3/client/petstore/python-experimental/tests/test_deserialization.py
+++ b/samples/openapi3/client/petstore/python-experimental/tests/test_deserialization.py
@@ -16,6 +16,20 @@
 import datetime
 
 import petstore_api
+from petstore_api.model import (
+    shape,
+    equilateral_triangle,
+    animal,
+    dog,
+    apple,
+    mammal,
+    whale,
+    zebra,
+    banana,
+    fruit_req,
+    drawing,
+    banana_req,
+)
 
 
 MockResponse = namedtuple('MockResponse', 'data')
@@ -46,8 +60,8 @@ def test_deserialize_shape(self):
         }
         response = MockResponse(data=json.dumps(data))
 
-        deserialized = self.deserialize(response, (petstore_api.Shape,), True)
-        self.assertTrue(isinstance(deserialized, petstore_api.EquilateralTriangle))
+        deserialized = self.deserialize(response, (shape.Shape,), True)
+        self.assertTrue(isinstance(deserialized, equilateral_triangle.EquilateralTriangle))
         self.assertEqual(deserialized.shape_type, shape_type)
         self.assertEqual(deserialized.triangle_type, triangle_type)
 
@@ -67,7 +81,7 @@ def test_deserialize_shape(self):
             petstore_api.ApiValueError,
             err_msg.format("quadrilateralType", "Triangle")
         ):
-            self.deserialize(response, (petstore_api.Shape,), True)
+            self.deserialize(response, (shape.Shape,), True)
 
     def test_deserialize_animal(self):
         """
@@ -86,8 +100,8 @@ def test_deserialize_animal(self):
         }
         response = MockResponse(data=json.dumps(data))
 
-        deserialized = self.deserialize(response, (petstore_api.Animal,), True)
-        self.assertTrue(isinstance(deserialized, petstore_api.Dog))
+        deserialized = self.deserialize(response, (animal.Animal,), True)
+        self.assertTrue(isinstance(deserialized, dog.Dog))
         self.assertEqual(deserialized.class_name, class_name)
         self.assertEqual(deserialized.color, color)
         self.assertEqual(deserialized.breed, breed)
@@ -98,15 +112,15 @@ def test_regex_constraint(self):
         """
 
         # Test with valid regex pattern.
-        inst = petstore_api.Apple(
+        inst = apple.Apple(
             cultivar="Akane"
         )
-        assert isinstance(inst, petstore_api.Apple)
+        assert isinstance(inst, apple.Apple)
 
-        inst = petstore_api.Apple(
+        inst = apple.Apple(
             origin="cHiLe"
         )
-        assert isinstance(inst, petstore_api.Apple)
+        assert isinstance(inst, apple.Apple)
 
         # Test with invalid regex pattern.
         err_msg = ("Invalid value for `{}`, must match regular expression `{}`$")
@@ -114,7 +128,7 @@ def test_regex_constraint(self):
             petstore_api.ApiValueError,
             err_msg.format("cultivar", "[^`]*")
         ):
-            inst = petstore_api.Apple(
+            inst = apple.Apple(
                 cultivar="!@#%@$#Akane"
             )
 
@@ -123,7 +137,7 @@ def test_regex_constraint(self):
             petstore_api.ApiValueError,
             err_msg.format("origin", "[^`]*")
         ):
-            inst = petstore_api.Apple(
+            inst = apple.Apple(
                 origin="!@#%@$#Chile"
             )
 
@@ -143,8 +157,8 @@ def test_deserialize_mammal(self):
             'className': class_name
         }
         response = MockResponse(data=json.dumps(data))
-        deserialized = self.deserialize(response, (petstore_api.Mammal,), True)
-        self.assertTrue(isinstance(deserialized, petstore_api.Whale))
+        deserialized = self.deserialize(response, (mammal.Mammal,), True)
+        self.assertTrue(isinstance(deserialized, whale.Whale))
         self.assertEqual(deserialized.has_baleen, has_baleen)
         self.assertEqual(deserialized.has_teeth, has_teeth)
         self.assertEqual(deserialized.class_name, class_name)
@@ -157,8 +171,8 @@ def test_deserialize_mammal(self):
             'className': class_name
         }
         response = MockResponse(data=json.dumps(data))
-        deserialized = self.deserialize(response, (petstore_api.Mammal,), True)
-        self.assertTrue(isinstance(deserialized, petstore_api.Zebra))
+        deserialized = self.deserialize(response, (mammal.Mammal,), True)
+        self.assertTrue(isinstance(deserialized, zebra.Zebra))
         self.assertEqual(deserialized.type, zebra_type)
         self.assertEqual(deserialized.class_name, class_name)
 
@@ -170,8 +184,8 @@ def test_deserialize_float_value(self):
           'lengthCm': 3.1415
         }
         response = MockResponse(data=json.dumps(data))
-        deserialized = self.deserialize(response, (petstore_api.Banana,), True)
-        self.assertTrue(isinstance(deserialized, petstore_api.Banana))
+        deserialized = self.deserialize(response, (banana.Banana,), True)
+        self.assertTrue(isinstance(deserialized, banana.Banana))
         self.assertEqual(deserialized.length_cm, 3.1415)
 
         # Float value is serialized without decimal point
@@ -179,8 +193,8 @@ def test_deserialize_float_value(self):
           'lengthCm': 3
         }
         response = MockResponse(data=json.dumps(data))
-        deserialized = self.deserialize(response, (petstore_api.Banana,), True)
-        self.assertTrue(isinstance(deserialized, petstore_api.Banana))
+        deserialized = self.deserialize(response, (banana.Banana,), True)
+        self.assertTrue(isinstance(deserialized, banana.Banana))
         self.assertEqual(deserialized.length_cm, 3.0)
 
     def test_deserialize_fruit_null_value(self):
@@ -192,10 +206,10 @@ def test_deserialize_fruit_null_value(self):
         # Unmarshal 'null' value
         data = None
         response = MockResponse(data=json.dumps(data))
-        deserialized = self.deserialize(response, (petstore_api.FruitReq, type(None)), True)
+        deserialized = self.deserialize(response, (fruit_req.FruitReq, type(None)), True)
         self.assertEqual(type(deserialized), type(None))
 
-        inst = petstore_api.FruitReq(None)
+        inst = fruit_req.FruitReq(None)
         self.assertIsNone(inst)
 
     def test_deserialize_with_additional_properties(self):
@@ -220,8 +234,8 @@ def test_deserialize_with_additional_properties(self):
             'size': 'medium',
         }
         response = MockResponse(data=json.dumps(data))
-        deserialized = self.deserialize(response, (petstore_api.Dog,), True)
-        self.assertEqual(type(deserialized), petstore_api.Dog)
+        deserialized = self.deserialize(response, (dog.Dog,), True)
+        self.assertEqual(type(deserialized), dog.Dog)
         self.assertEqual(deserialized.class_name, 'Dog')
         self.assertEqual(deserialized.breed, 'golden retriever')
 
@@ -238,8 +252,8 @@ def test_deserialize_with_additional_properties(self):
             'p2': [ 'a', 'b', 123],
         }
         response = MockResponse(data=json.dumps(data))
-        deserialized = self.deserialize(response, (petstore_api.Mammal,), True)
-        self.assertEqual(type(deserialized), petstore_api.Zebra)
+        deserialized = self.deserialize(response, (mammal.Mammal,), True)
+        self.assertEqual(type(deserialized), zebra.Zebra)
         self.assertEqual(deserialized.class_name, 'zebra')
         self.assertEqual(deserialized.type, 'plains')
         self.assertEqual(deserialized.p1, True)
@@ -259,8 +273,8 @@ def test_deserialize_with_additional_properties(self):
                 'unknown-group': 'abc',
             }
             response = MockResponse(data=json.dumps(data))
-            deserialized = self.deserialize(response, (petstore_api.BananaReq,), True)
-            self.assertEqual(type(deserialized), petstore_api.BananaReq)
+            deserialized = self.deserialize(response, (banana_req.BananaReq,), True)
+            self.assertEqual(type(deserialized), banana_req.BananaReq)
             self.assertEqual(deserialized.lengthCm, 21)
             self.assertEqual(deserialized.p1, True)
 
@@ -286,4 +300,4 @@ def test_deserialize_with_additional_properties_and_reference(self):
             ],
         }
         response = MockResponse(data=json.dumps(data))
-        deserialized = self.deserialize(response, (petstore_api.Drawing,), True)
+        deserialized = self.deserialize(response, (drawing.Drawing,), True)
diff --git a/samples/openapi3/client/petstore/python-experimental/tests/test_discard_unknown_properties.py b/samples/openapi3/client/petstore/python-experimental/tests/test_discard_unknown_properties.py
index a85ae29c46e2..976a3da2df4f 100644
--- a/samples/openapi3/client/petstore/python-experimental/tests/test_discard_unknown_properties.py
+++ b/samples/openapi3/client/petstore/python-experimental/tests/test_discard_unknown_properties.py
@@ -12,18 +12,12 @@
 """
 from collections import namedtuple
 import json
-import os
 import re
-import shutil
 import unittest
-from six.moves.urllib.parse import urlencode, urlparse
 
 import petstore_api
+from petstore_api.model import cat, dog, isosceles_triangle, banana_req
 from petstore_api import Configuration, signing
-from petstore_api.rest import (
-    RESTClientObject,
-    RESTResponse
-)
 
 from petstore_api.model_utils import (
     file_type,
@@ -57,7 +51,7 @@ def test_deserialize_banana_req_do_not_discard_unknown_properties(self):
         # Deserializing with strict validation raises an exception because the 'unknown_property'
         # is undeclared.
         with self.assertRaises(petstore_api.exceptions.ApiAttributeError) as cm:
-            deserialized = api_client.deserialize(response, ((petstore_api.BananaReq),), True)
+            deserialized = api_client.deserialize(response, ((banana_req.BananaReq),), True)
         self.assertTrue(re.match("BananaReq has no attribute 'unknown_property' at.*", str(cm.exception)),
             'Exception message: {0}'.format(str(cm.exception)))
 
@@ -83,7 +77,7 @@ def test_deserialize_isosceles_triangle_do_not_discard_unknown_properties(self):
         # Deserializing with strict validation raises an exception because the 'unknown_property'
         # is undeclared.
         with self.assertRaises(petstore_api.ApiValueError) as cm:
-            deserialized = api_client.deserialize(response, ((petstore_api.IsoscelesTriangle),), True)
+            deserialized = api_client.deserialize(response, ((isosceles_triangle.IsoscelesTriangle),), True)
         self.assertTrue(re.match('.*Not all inputs were used.*unknown_property.*', str(cm.exception)),
             'Exception message: {0}'.format(str(cm.exception)))
 
@@ -107,8 +101,8 @@ def test_deserialize_banana_req_discard_unknown_properties(self):
         # The 'unknown_property' is undeclared, which would normally raise an exception, but
         # when discard_unknown_keys is set to True, the unknown properties are discarded.
         response = MockResponse(data=json.dumps(data))
-        deserialized = api_client.deserialize(response, ((petstore_api.BananaReq),), True)
-        self.assertTrue(isinstance(deserialized, petstore_api.BananaReq))
+        deserialized = api_client.deserialize(response, ((banana_req.BananaReq),), True)
+        self.assertTrue(isinstance(deserialized, banana_req.BananaReq))
         # Check the 'unknown_property' and 'more-unknown' properties are not present in the
         # output.
         self.assertIn("length_cm", deserialized.to_dict().keys())
@@ -133,8 +127,8 @@ def test_deserialize_cat_do_not_discard_unknown_properties(self):
         # Deserializing with strict validation does not raise an exception because the even though
         # the 'dynamic-property' is undeclared, the 'Cat' schema defines the additionalProperties
         # attribute.
-        deserialized = api_client.deserialize(response, ((petstore_api.Cat),), True)
-        self.assertTrue(isinstance(deserialized, petstore_api.Cat))
+        deserialized = api_client.deserialize(response, ((cat.Cat),), True)
+        self.assertTrue(isinstance(deserialized, cat.Cat))
         self.assertIn('color', deserialized.to_dict())
         self.assertEqual(deserialized['color'], 'black')
 
@@ -156,8 +150,8 @@ def test_deserialize_cat_discard_unknown_properties(self):
         # The 'my_additional_property' is undeclared, but 'Cat' has a 'Address' type through
         # the allOf: [ $ref: '#/components/schemas/Address' ].
         response = MockResponse(data=json.dumps(data))
-        deserialized = api_client.deserialize(response, ((petstore_api.Cat),), True)
-        self.assertTrue(isinstance(deserialized, petstore_api.Cat))
+        deserialized = api_client.deserialize(response, ((cat.Cat),), True)
+        self.assertTrue(isinstance(deserialized, cat.Cat))
         # Check the 'unknown_property' and 'more-unknown' properties are not present in the
         # output.
         self.assertIn("declawed", deserialized.to_dict().keys())
diff --git a/samples/openapi3/client/petstore/python-experimental/tests/test_http_signature.py b/samples/openapi3/client/petstore/python-experimental/tests/test_http_signature.py
index 9864cf1a2139..e8f0dd186a98 100644
--- a/samples/openapi3/client/petstore/python-experimental/tests/test_http_signature.py
+++ b/samples/openapi3/client/petstore/python-experimental/tests/test_http_signature.py
@@ -25,6 +25,8 @@
 from six.moves.urllib.parse import urlencode, urlparse
 
 import petstore_api
+from petstore_api.model import category, tag, pet
+from petstore_api.api.pet_api import PetApi
 from petstore_api import Configuration, signing
 from petstore_api.rest import (
     RESTClientObject,
@@ -211,13 +213,13 @@ def tearDownClass(cls):
 
     @classmethod
     def setUpModels(cls):
-        cls.category = petstore_api.Category()
+        cls.category = category.Category()
         cls.category.id = id_gen()
         cls.category.name = "dog"
-        cls.tag = petstore_api.Tag()
+        cls.tag = tag.Tag()
         cls.tag.id = id_gen()
         cls.tag.name = "python-pet-tag"
-        cls.pet = petstore_api.Pet(
+        cls.pet = pet.Pet(
             name="hello kity",
             photo_urls=["http://foo.bar.com/1", "http://foo.bar.com/2"]
         )
@@ -286,7 +288,7 @@ def test_valid_http_signature(self):
         config.access_token = None
 
         api_client = petstore_api.ApiClient(config)
-        pet_api = petstore_api.PetApi(api_client)
+        pet_api = PetApi(api_client)
 
         mock_pool = MockPoolManager(self)
         api_client.rest_client.pool_manager = mock_pool
@@ -317,7 +319,7 @@ def test_valid_http_signature_with_defaults(self):
         config.access_token = None
 
         api_client = petstore_api.ApiClient(config)
-        pet_api = petstore_api.PetApi(api_client)
+        pet_api = PetApi(api_client)
 
         mock_pool = MockPoolManager(self)
         api_client.rest_client.pool_manager = mock_pool
@@ -353,7 +355,7 @@ def test_valid_http_signature_rsassa_pkcs1v15(self):
         config.access_token = None
 
         api_client = petstore_api.ApiClient(config)
-        pet_api = petstore_api.PetApi(api_client)
+        pet_api = PetApi(api_client)
 
         mock_pool = MockPoolManager(self)
         api_client.rest_client.pool_manager = mock_pool
@@ -389,7 +391,7 @@ def test_valid_http_signature_rsassa_pss(self):
         config.access_token = None
 
         api_client = petstore_api.ApiClient(config)
-        pet_api = petstore_api.PetApi(api_client)
+        pet_api = PetApi(api_client)
 
         mock_pool = MockPoolManager(self)
         api_client.rest_client.pool_manager = mock_pool
@@ -425,7 +427,7 @@ def test_valid_http_signature_ec_p521(self):
         config.access_token = None
 
         api_client = petstore_api.ApiClient(config)
-        pet_api = petstore_api.PetApi(api_client)
+        pet_api = PetApi(api_client)
 
         mock_pool = MockPoolManager(self)
         api_client.rest_client.pool_manager = mock_pool