Ensure PEP0561 compliance for proto stubs.

PiperOrigin-RevId: 339362317

py/MANIFEST.in

@@ -2,5 +2,6 @@
 include requirements.txt
 include README.md
 include google/fhir/py.typed
+include proto/google/fhir/proto/py.typed
 recursive-include proto/google/fhir/proto *.pyi
 global-exclude *_test.py

py/setup.py

@@ -43,14 +43,18 @@
 
 
 def _generate_python_protos(proto_files: List[str], *, python_out: str = '.'):
-  """Generates FHIR R4 Python protobuf classes.
+  """Generates FHIR Python protobuf classes.
 
   Args:
     proto_files: A list of .proto file paths.
     python_out: Indicates where the generated definitions should be placed.
       Defaults to '.', which indicates to place alongside the .proto definition.
       This directory will be created if it does not exist.
   """
+  if not proto_files:
+    return
+
+  subpackages = []
   for proto_file in proto_files:
     proto_dir = os.path.dirname(os.path.abspath(proto_file))
 
@@ -61,7 +65,9 @@ def _generate_python_protos(proto_files: List[str], *, python_out: str = '.'):
     # Create Python package
     init_py = os.path.join(python_out, relpath, '__init__.py')
     if not os.path.exists(init_py):
-      pathlib.Path(os.path.dirname(init_py)).mkdir(parents=True)
+      subpackage = os.path.dirname(init_py)
+      subpackages.append(subpackage)
+      pathlib.Path(subpackage).mkdir(parents=True)
       pathlib.Path(init_py).touch()
 
     # Generate _py_pb2.py file
@@ -81,6 +87,10 @@ def _generate_python_protos(proto_files: List[str], *, python_out: str = '.'):
       if subprocess.call(protoc_cmd) != 0:
         sys.exit(-1)
 
+  # Add py.typed for PEP0561 compliance
+  root_package = os.path.commonpath(subpackages)
+  pathlib.Path(os.path.join(root_package, 'py.typed')).touch()
+
 
 def _parse_requirements(path: str) -> List[str]:
   """Parses a requirements.txt file into a list of strings."""