[python] : Make example code snippet compilable (#3148)

* feat(python): Making example compilable

* feat(python): Updating pet project

* feat(python): Updating comments

* feat(documentation): Fixing comments style

* feat(documentation): Updating documentation

* feat(documentation): Fixing comments style

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

@@ -35,7 +35,7 @@ import petstore_api
 from petstore_api.rest import ApiException
 from pprint import pprint
 
-# create an instance of the API class
+# Create an instance of the API class
 api_instance = petstore_api.FakeApi()
 xml_item = petstore_api.XmlItem() # XmlItem | XmlItem Body
 
@@ -88,7 +88,7 @@ import petstore_api
 from petstore_api.rest import ApiException
 from pprint import pprint
 
-# create an instance of the API class
+# Create an instance of the API class
 api_instance = petstore_api.FakeApi()
 body = True # bool | Input boolean as post body (optional)
 
@@ -141,7 +141,7 @@ import petstore_api
 from petstore_api.rest import ApiException
 from pprint import pprint
 
-# create an instance of the API class
+# Create an instance of the API class
 api_instance = petstore_api.FakeApi()
 body = petstore_api.OuterComposite() # OuterComposite | Input composite as post body (optional)
 
@@ -194,7 +194,7 @@ import petstore_api
 from petstore_api.rest import ApiException
 from pprint import pprint
 
-# create an instance of the API class
+# Create an instance of the API class
 api_instance = petstore_api.FakeApi()
 body = 3.4 # float | Input number as post body (optional)
 
@@ -247,7 +247,7 @@ import petstore_api
 from petstore_api.rest import ApiException
 from pprint import pprint
 
-# create an instance of the API class
+# Create an instance of the API class
 api_instance = petstore_api.FakeApi()
 body = 'body_example' # str | Input string as post body (optional)
 
@@ -300,7 +300,7 @@ import petstore_api
 from petstore_api.rest import ApiException
 from pprint import pprint
 
-# create an instance of the API class
+# Create an instance of the API class
 api_instance = petstore_api.FakeApi()
 body = petstore_api.FileSchemaTestClass() # FileSchemaTestClass | 
 
@@ -350,7 +350,7 @@ import petstore_api
 from petstore_api.rest import ApiException
 from pprint import pprint
 
-# create an instance of the API class
+# Create an instance of the API class
 api_instance = petstore_api.FakeApi()
 query = 'query_example' # str | 
 body = petstore_api.User() # User | 
@@ -404,7 +404,7 @@ import petstore_api
 from petstore_api.rest import ApiException
 from pprint import pprint
 
-# create an instance of the API class
+# Create an instance of the API class
 api_instance = petstore_api.FakeApi()
 body = petstore_api.Client() # Client | client model
 
@@ -463,7 +463,9 @@ configuration = petstore_api.Configuration()
 configuration.username = 'YOUR_USERNAME'
 configuration.password = 'YOUR_PASSWORD'
 
-# create an instance of the API class
+# Defining host is optional and default to http://petstore.swagger.io:80/v2
+configuration.host = "http://petstore.swagger.io:80/v2"
+# Create an instance of the API class
 api_instance = petstore_api.FakeApi(petstore_api.ApiClient(configuration))
 number = 3.4 # float | None
 double = 3.4 # float | None
@@ -543,7 +545,7 @@ import petstore_api
 from petstore_api.rest import ApiException
 from pprint import pprint
 
-# create an instance of the API class
+# Create an instance of the API class
 api_instance = petstore_api.FakeApi()
 enum_header_string_array = ['enum_header_string_array_example'] # list[str] | Header parameter enum test (string array) (optional)
 enum_header_string = '-efg' # str | Header parameter enum test (string) (optional) (default to '-efg')
@@ -611,7 +613,7 @@ import petstore_api
 from petstore_api.rest import ApiException
 from pprint import pprint
 
-# create an instance of the API class
+# Create an instance of the API class
 api_instance = petstore_api.FakeApi()
 required_string_group = 56 # int | Required String in group parameters
 required_boolean_group = True # bool | Required Boolean in group parameters
@@ -672,7 +674,7 @@ import petstore_api
 from petstore_api.rest import ApiException
 from pprint import pprint
 
-# create an instance of the API class
+# Create an instance of the API class
 api_instance = petstore_api.FakeApi()
 param = {'key': 'param_example'} # dict(str, str) | request body
 
@@ -723,7 +725,7 @@ import petstore_api
 from petstore_api.rest import ApiException
 from pprint import pprint
 
-# create an instance of the API class
+# Create an instance of the API class
 api_instance = petstore_api.FakeApi()
 param = 'param_example' # str | field1
 param2 = 'param2_example' # str | field2