[PYTHON] Api doc python with multiple authentications (#928)

* [PYTHON] better code snippet for API usage with authentication

* update python samples

samples/client/petstore/python-asyncio/docs/FakeApi.md

@@ -353,6 +353,8 @@ Fake endpoint for testing various parameters 假端點 偽のエンドポイン
 Fake endpoint for testing various parameters 假端點 偽のエンドポイント 가짜 엔드 포인트 
 
 ### Example
+
+* Basic Authentication (http_basic_test): 
 ```python
 from __future__ import print_function
 import time

samples/client/petstore/python-asyncio/docs/FakeClassnameTags123Api.md

@@ -15,6 +15,8 @@ To test class name in snake case
 To test class name in snake case
 
 ### Example
+
+* Api Key Authentication (api_key_query): 
 ```python
 from __future__ import print_function
 import time

samples/client/petstore/python-asyncio/docs/PetApi.md

@@ -21,6 +21,8 @@ Method | HTTP request | Description
 Add a new pet to the store
 
 ### Example
+
+* OAuth Authentication (petstore_auth): 
 ```python
 from __future__ import print_function
 import time
@@ -70,6 +72,8 @@ void (empty response body)
 Deletes a pet
 
 ### Example
+
+* OAuth Authentication (petstore_auth): 
 ```python
 from __future__ import print_function
 import time
@@ -123,6 +127,8 @@ Finds Pets by status
 Multiple status values can be provided with comma separated strings
 
 ### Example
+
+* OAuth Authentication (petstore_auth): 
 ```python
 from __future__ import print_function
 import time
@@ -175,6 +181,8 @@ Finds Pets by tags
 Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
 
 ### Example
+
+* OAuth Authentication (petstore_auth): 
 ```python
 from __future__ import print_function
 import time
@@ -227,6 +235,8 @@ Find pet by ID
 Returns a single pet
 
 ### Example
+
+* Api Key Authentication (api_key): 
 ```python
 from __future__ import print_function
 import time
@@ -279,6 +289,8 @@ Name | Type | Description  | Notes
 Update an existing pet
 
 ### Example
+
+* OAuth Authentication (petstore_auth): 
 ```python
 from __future__ import print_function
 import time
@@ -328,6 +340,8 @@ void (empty response body)
 Updates a pet in the store with form data
 
 ### Example
+
+* OAuth Authentication (petstore_auth): 
 ```python
 from __future__ import print_function
 import time
@@ -381,6 +395,8 @@ void (empty response body)
 uploads an image
 
 ### Example
+
+* OAuth Authentication (petstore_auth): 
 ```python
 from __future__ import print_function
 import time
@@ -435,6 +451,8 @@ Name | Type | Description  | Notes
 uploads an image (required)
 
 ### Example
+
+* OAuth Authentication (petstore_auth): 
 ```python
 from __future__ import print_function
 import time

samples/client/petstore/python-asyncio/docs/StoreApi.md

@@ -65,6 +65,8 @@ Returns pet inventories by status
 Returns a map of status codes to quantities
 
 ### Example
+
+* Api Key Authentication (api_key): 
 ```python
 from __future__ import print_function
 import time