[Python] fix object arrays giving mypy error "Incompatible types in assignment" in to_dict() (#19223)

* [python] mypy fix for multiple arrays of objects

* [python] mypy test for multiple arrays of objects

samples/openapi3/client/petstore/python-pydantic-v1-aiohttp/.openapi-generator/FILES

@@ -66,6 +66,7 @@ docs/MapTest.md
 docs/MixedPropertiesAndAdditionalPropertiesClass.md
 docs/Model200Response.md
 docs/ModelReturn.md
+docs/MultiArrays.md
 docs/Name.md
 docs/NullableClass.md
 docs/NullableProperty.md
@@ -188,6 +189,7 @@ 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/multi_arrays.py
 petstore_api/models/name.py
 petstore_api/models/nullable_class.py
 petstore_api/models/nullable_property.py

samples/openapi3/client/petstore/python-pydantic-v1-aiohttp/README.md

@@ -209,6 +209,7 @@ Class | Method | HTTP request | Description
  - [MixedPropertiesAndAdditionalPropertiesClass](docs/MixedPropertiesAndAdditionalPropertiesClass.md)
  - [Model200Response](docs/Model200Response.md)
  - [ModelReturn](docs/ModelReturn.md)
+ - [MultiArrays](docs/MultiArrays.md)
  - [Name](docs/Name.md)
  - [NullableClass](docs/NullableClass.md)
  - [NullableProperty](docs/NullableProperty.md)

samples/openapi3/client/petstore/python-pydantic-v1-aiohttp/docs/MultiArrays.md

@@ -0,0 +1,29 @@
+# MultiArrays
+
+
+## Properties
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+**tags** | [**List[Tag]**](Tag.md) |  | [optional] 
+**files** | [**List[File]**](File.md) | Another array of objects in addition to tags (mypy check to not to reuse the same iterator) | [optional] 
+
+## Example
+
+```python
+from petstore_api.models.multi_arrays import MultiArrays
+
+# TODO update the JSON string below
+json = "{}"
+# create an instance of MultiArrays from a JSON string
+multi_arrays_instance = MultiArrays.from_json(json)
+# print the JSON string representation of the object
+print MultiArrays.to_json()
+
+# convert the object into a dict
+multi_arrays_dict = multi_arrays_instance.to_dict()
+# create an instance of MultiArrays from a dict
+multi_arrays_from_dict = MultiArrays.from_dict(multi_arrays_dict)
+```
+[[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
+
+

samples/openapi3/client/petstore/python-pydantic-v1-aiohttp/petstore_api/__init__.py

@@ -97,6 +97,7 @@ 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.multi_arrays import MultiArrays
 from petstore_api.models.name import Name
 from petstore_api.models.nullable_class import NullableClass
 from petstore_api.models.nullable_property import NullableProperty

samples/openapi3/client/petstore/python-pydantic-v1-aiohttp/petstore_api/models/__init__.py

@@ -72,6 +72,7 @@ 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.multi_arrays import MultiArrays
 from petstore_api.models.name import Name
 from petstore_api.models.nullable_class import NullableClass
 from petstore_api.models.nullable_property import NullableProperty

samples/openapi3/client/petstore/python-pydantic-v1-aiohttp/petstore_api/models/multi_arrays.py

@@ -0,0 +1,89 @@
+# 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: \" \\
+
+    The version of the OpenAPI document: 1.0.0
+    Generated by OpenAPI Generator (https://openapi-generator.tech)
+
+    Do not edit the class manually.
+"""  # noqa: E501
+
+
+from __future__ import annotations
+import pprint
+import re  # noqa: F401
+import json
+
+
+from typing import List, Optional
+from pydantic import BaseModel, Field, conlist
+from petstore_api.models.file import File
+from petstore_api.models.tag import Tag
+
+class MultiArrays(BaseModel):
+    """
+    MultiArrays
+    """
+    tags: Optional[conlist(Tag)] = None
+    files: Optional[conlist(File)] = Field(default=None, description="Another array of objects in addition to tags (mypy check to not to reuse the same iterator)")
+    __properties = ["tags", "files"]
+
+    class Config:
+        """Pydantic configuration"""
+        allow_population_by_field_name = True
+        validate_assignment = True
+
+    def to_str(self) -> str:
+        """Returns the string representation of the model using alias"""
+        return pprint.pformat(self.dict(by_alias=True))
+
+    def to_json(self) -> str:
+        """Returns the JSON representation of the model using alias"""
+        return json.dumps(self.to_dict())
+
+    @classmethod
+    def from_json(cls, json_str: str) -> MultiArrays:
+        """Create an instance of MultiArrays from a JSON string"""
+        return cls.from_dict(json.loads(json_str))
+
+    def to_dict(self):
+        """Returns the dictionary representation of the model using alias"""
+        _dict = self.dict(by_alias=True,
+                          exclude={
+                          },
+                          exclude_none=True)
+        # override the default output from pydantic by calling `to_dict()` of each item in tags (list)
+        _items = []
+        if self.tags:
+            for _item in self.tags:
+                if _item:
+                    _items.append(_item.to_dict())
+            _dict['tags'] = _items
+        # override the default output from pydantic by calling `to_dict()` of each item in files (list)
+        _items = []
+        if self.files:
+            for _item in self.files:
+                if _item:
+                    _items.append(_item.to_dict())
+            _dict['files'] = _items
+        return _dict
+
+    @classmethod
+    def from_dict(cls, obj: dict) -> MultiArrays:
+        """Create an instance of MultiArrays from a dict"""
+        if obj is None:
+            return None
+
+        if not isinstance(obj, dict):
+            return MultiArrays.parse_obj(obj)
+
+        _obj = MultiArrays.parse_obj({
+            "tags": [Tag.from_dict(_item) for _item in obj.get("tags")] if obj.get("tags") is not None else None,
+            "files": [File.from_dict(_item) for _item in obj.get("files")] if obj.get("files") is not None else None
+        })
+        return _obj
+
+

samples/openapi3/client/petstore/python-pydantic-v1-aiohttp/test/test_multi_arrays.py

@@ -0,0 +1,60 @@
+# 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: \" \\
+
+    The version of the OpenAPI document: 1.0.0
+    Generated by OpenAPI Generator (https://openapi-generator.tech)
+
+    Do not edit the class manually.
+"""  # noqa: E501
+
+
+import unittest
+import datetime
+
+from petstore_api.models.multi_arrays import MultiArrays  # noqa: E501
+
+class TestMultiArrays(unittest.TestCase):
+    """MultiArrays unit test stubs"""
+
+    def setUp(self):
+        pass
+
+    def tearDown(self):
+        pass
+
+    def make_instance(self, include_optional) -> MultiArrays:
+        """Test MultiArrays
+            include_option is a boolean, when False only required
+            params are included, when True both required and
+            optional params are included """
+        # uncomment below to create an instance of `MultiArrays`
+        """
+        model = MultiArrays()  # noqa: E501
+        if include_optional:
+            return MultiArrays(
+                tags = [
+                    petstore_api.models.tag.Tag(
+                        id = 56, 
+                        name = '', )
+                    ],
+                files = [
+                    petstore_api.models.file.File(
+                        source_uri = '', )
+                    ]
+            )
+        else:
+            return MultiArrays(
+        )
+        """
+
+    def testMultiArrays(self):
+        """Test MultiArrays"""
+        # inst_req_only = self.make_instance(include_optional=False)
+        # inst_req_and_optional = self.make_instance(include_optional=True)
+
+if __name__ == '__main__':
+    unittest.main()