drop support of deprecated /labs/ and replace it with v2

Author: boogheta

twitter/api.py

@@ -393,7 +393,7 @@ def _handle_response(self, req, uri, arg_data, _timeout=None):
                 data = f.read()
             if len(data) == 0:
                 return wrap_response({}, handle.headers)
-            elif "json" == self.format or "/labs/" in uri:
+            elif "json" == self.format or uri.startswith("2/"):
                 try:
                     res = json.loads(data.decode('utf8'))
                 except json.decoder.JSONDecodeError as e: