[Python] Add echo_api test object serialization for multipart requests (#18176)

* [python] echo add test object serialization for multipart requests

* [echo api] update samples

* [echo api] update samples

samples/client/echo_api/python/docs/FormApi.md

@@ -5,6 +5,7 @@ All URIs are relative to *http://localhost:3000*
 Method | HTTP request | Description
 ------------- | ------------- | -------------
 [**test_form_integer_boolean_string**](FormApi.md#test_form_integer_boolean_string) | **POST** /form/integer/boolean/string | Test form parameter(s)
+[**test_form_object_multipart**](FormApi.md#test_form_object_multipart) | **POST** /form/object/multipart | Test form parameter(s) for multipart schema
 [**test_form_oneof**](FormApi.md#test_form_oneof) | **POST** /form/oneof | Test form parameter(s) for oneOf schema
 
 
@@ -79,6 +80,74 @@ No authorization required
 
 [[Back to top]](#) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to Model list]](../README.md#documentation-for-models) [[Back to README]](../README.md)
 
+# **test_form_object_multipart**
+> str test_form_object_multipart(marker)
+
+Test form parameter(s) for multipart schema
+
+Test form parameter(s) for multipart schema
+
+### Example
+
+
+```python
+import openapi_client
+from openapi_client.models.test_form_object_multipart_request_marker import TestFormObjectMultipartRequestMarker
+from openapi_client.rest import ApiException
+from pprint import pprint
+
+# Defining the host is optional and defaults to http://localhost:3000
+# See configuration.py for a list of all supported configuration parameters.
+configuration = openapi_client.Configuration(
+    host = "http://localhost:3000"
+)
+
+
+# Enter a context with an instance of the API client
+with openapi_client.ApiClient(configuration) as api_client:
+    # Create an instance of the API class
+    api_instance = openapi_client.FormApi(api_client)
+    marker = openapi_client.TestFormObjectMultipartRequestMarker() # TestFormObjectMultipartRequestMarker | 
+
+    try:
+        # Test form parameter(s) for multipart schema
+        api_response = api_instance.test_form_object_multipart(marker)
+        print("The response of FormApi->test_form_object_multipart:\n")
+        pprint(api_response)
+    except Exception as e:
+        print("Exception when calling FormApi->test_form_object_multipart: %s\n" % e)
+```
+
+
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **marker** | [**TestFormObjectMultipartRequestMarker**](TestFormObjectMultipartRequestMarker.md)|  | 
+
+### Return type
+
+**str**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: multipart/form-data
+ - **Accept**: text/plain
+
+### HTTP response details
+
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+**200** | Successful operation |  -  |
+
+[[Back to top]](#) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to Model list]](../README.md#documentation-for-models) [[Back to README]](../README.md)
+
 # **test_form_oneof**
 > str test_form_oneof(form1=form1, form2=form2, form3=form3, form4=form4, id=id, name=name)
 

samples/client/echo_api/python/docs/TestFormObjectMultipartRequestMarker.md

@@ -0,0 +1,29 @@
+# TestFormObjectMultipartRequestMarker
+
+
+## Properties
+
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+**name** | **str** |  | [optional] 
+
+## Example
+
+```python
+from openapi_client.models.test_form_object_multipart_request_marker import TestFormObjectMultipartRequestMarker
+
+# TODO update the JSON string below
+json = "{}"
+# create an instance of TestFormObjectMultipartRequestMarker from a JSON string
+test_form_object_multipart_request_marker_instance = TestFormObjectMultipartRequestMarker.from_json(json)
+# print the JSON string representation of the object
+print(TestFormObjectMultipartRequestMarker.to_json())
+
+# convert the object into a dict
+test_form_object_multipart_request_marker_dict = test_form_object_multipart_request_marker_instance.to_dict()
+# create an instance of TestFormObjectMultipartRequestMarker from a dict
+test_form_object_multipart_request_marker_form_dict = test_form_object_multipart_request_marker.from_dict(test_form_object_multipart_request_marker_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)
+
+