def _real_extract(self, url):
         video_id = self._match_id(url)
 
     def _real_extract(self, url):
         video_id = self._match_id(url)
 
         data = self._download_json(json_url, video_id)
 
         def get_optional(data_dict, field):
         data = self._download_json(json_url, video_id)
 
         def get_optional(data_dict, field):