Cannot generate a JSON schema for a models with Deque field

[sergejkozin]

Checks

• I added a descriptive title to this issue
• I have searched (google, github) for similar issues and couldn't find anything
• I have read and followed the docs and still think this is a bug

Bug

Output of python -c "import pydantic.utils; print(pydantic.utils.version_info())":

             pydantic version: 1.8.2
            pydantic compiled: False
                 install path: /home/sergej/Projects/pydantic/pydantic
               python version: 3.8.5 (default, Jan 27 2021, 15:41:15)  [GCC 9.3.0]
                     platform: Linux-5.4.0-72-generic-x86_64-with-glibc2.29
     optional deps. installed: ['devtools', 'dotenv', 'email-validator', 'typing-extensions']

Description

The AssertionError occurs on JSON schema generation if Deque field used in the Pydantic model.

Example

from typing import Deque

from pydantic import BaseModel


class Model(BaseModel):
    a: Deque[str]


Model.schema()

Output

Traceback (most recent call last):
  File "/home/sergej/Projects/pydantic/test_deque.py", line 10, in <module>
    Model.schema()
  File "/home/sergej/Projects/pydantic/pydantic/main.py", line 720, in schema
    s = model_schema(cls, by_alias=by_alias, ref_template=ref_template)
  File "/home/sergej/Projects/pydantic/pydantic/schema.py", line 168, in model_schema
    m_schema, m_definitions, nested_models = model_process_schema(
  File "/home/sergej/Projects/pydantic/pydantic/schema.py", line 557, in model_process_schema
    m_schema, m_definitions, nested_models = model_type_schema(
  File "/home/sergej/Projects/pydantic/pydantic/schema.py", line 598, in model_type_schema
    f_schema, f_definitions, f_nested_models = field_schema(
  File "/home/sergej/Projects/pydantic/pydantic/schema.py", line 242, in field_schema
    f_schema, f_definitions, f_nested_models = field_type_schema(
  File "/home/sergej/Projects/pydantic/pydantic/schema.py", line 503, in field_type_schema
    assert field.shape in {SHAPE_SINGLETON, SHAPE_GENERIC}, field.shape
AssertionError: 11

[DarkAce65]

+1 to this. I just ran into the same error and confirmed that the linked PR fixes the bug