Update to serialization results (closes #3881).

docs/api-guide/serializers.md

@@ -43,7 +43,7 @@ We can now use `CommentSerializer` to serialize a comment, or list of comments.
 
     serializer = CommentSerializer(comment)
     serializer.data
-    # {'email': u'leila@example.com', 'content': u'foo bar', 'created': datetime.datetime(2012, 8, 22, 16, 20, 9, 822774)}
+    # {'email': 'leila@example.com', 'content': 'foo bar', 'created': '2016-01-27T15:17:10.375877'}
 
 At this point we've translated the model instance into Python native datatypes.  To finalise the serialization process we render the data into `json`.
 
@@ -51,7 +51,7 @@ At this point we've translated the model instance into Python native datatypes.
 
     json = JSONRenderer().render(serializer.data)
     json
-    # '{"email": "leila@example.com", "content": "foo bar", "created": "2012-08-22T16:20:09.822"}'
+    # b'{"email":"leila@example.com","content":"foo bar","created":"2016-01-27T15:17:10.375877"}'
 
 ## Deserializing objects