Fix problem in sanitize_for_serialization for Python (pydantic type SecretStr ) BUG#16086 (2nd pull) (#18023)

* fix-for-bug-16086

* add to_dict alternative

* fix assertEqual

* remove extra blank line + test_model Argument SecretStr set

* update samples / remove extra blank line

* restore sanitize test for serialization with different data types

* remove empty line in api_client.mustache

* remove 2nd empty line in api_client.mustache

samples/client/echo_api/python/openapi_client/api_client.py

@@ -24,6 +24,7 @@ import tempfile
 
 from urllib.parse import quote
 from typing import Tuple, Optional, List, Dict, Union
+from pydantic import SecretStr
 
 from openapi_client.configuration import Configuration
 from openapi_client.api_response import ApiResponse, T as ApiResponseT
@@ -337,6 +338,7 @@ class ApiClient:
         """Builds a JSON POST object.
 
         If obj is None, return None.
+        If obj is SecretStr, return obj.get_secret_value()
         If obj is str, int, long, float, bool, return directly.
         If obj is datetime.datetime, datetime.date
             convert to string in iso8601 format.
@@ -349,6 +351,8 @@ class ApiClient:
         """
         if obj is None:
             return None
+        elif isinstance(obj, SecretStr):
+            return obj.get_secret_value()
         elif isinstance(obj, self.PRIMITIVE_TYPES):
             return obj
         elif isinstance(obj, list):
@@ -370,7 +374,10 @@ class ApiClient:
             # and attributes which value is not None.
             # Convert attribute name to json key in
             # model definition for request.
-            obj_dict = obj.to_dict()
+            if hasattr(obj, 'to_dict') and callable(getattr(obj, 'to_dict')):
+                obj_dict = obj.to_dict()
+            else:
+                obj_dict = obj.__dict__
 
         return {
             key: self.sanitize_for_serialization(val)