[Python][Client] Python model directory init missing (#8215)

* include model and api dir init mustaches

* update examples

* remove unwanted changes

* revert unwanted changes in sample

Co-authored-by: aani <aani>

Author: code-lucidal58

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PythonClientCodegen.java

@@ -126,8 +126,8 @@ public void processOpts() {
 
         // add the models and apis folders
         supportingFiles.add(new SupportingFile("__init__models.mustache", packagePath() + File.separatorChar + "models", "__init__.py"));
+        supportingFiles.add(new SupportingFile("__init__model.mustache", packagePath() + File.separatorChar + "model", "__init__.py"));
         supportingFiles.add(new SupportingFile("__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 ?
            (openAPI.getComponents() != null ? openAPI.getComponents().getSecuritySchemes() : null) : null;

samples/client/petstore/python/.openapi-generator/FILES

@@ -84,6 +84,7 @@ 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

samples/openapi3/client/extensions/x-auth-id-alias/python/.openapi-generator/FILES

@@ -17,6 +17,7 @@ x_auth_id_alias/api_client.py
 x_auth_id_alias/apis/__init__.py
 x_auth_id_alias/configuration.py
 x_auth_id_alias/exceptions.py
+x_auth_id_alias/model/__init__.py
 x_auth_id_alias/model_utils.py
 x_auth_id_alias/models/__init__.py
 x_auth_id_alias/models/__init__.py

samples/openapi3/client/features/dynamic-servers/python/.openapi-generator/FILES

@@ -10,6 +10,7 @@ dynamic_servers/api_client.py
 dynamic_servers/apis/__init__.py
 dynamic_servers/configuration.py
 dynamic_servers/exceptions.py
+dynamic_servers/model/__init__.py
 dynamic_servers/model_utils.py
 dynamic_servers/models/__init__.py
 dynamic_servers/models/__init__.py

samples/openapi3/client/petstore/python/.openapi-generator/FILES

@@ -114,6 +114,7 @@ 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/additional_properties_with_array_of_enums.py
 petstore_api/model/address.py