code: def changeGroupImageRemote(self, image_url, thread_id=None):
          
          (image_id, mimetype), = self._upload(get_files_from_urls([image_url]))
          return self._changeGroupImage(image_id, thread_id)
docs: Changes a thread image from a URL
  
          :param image_url: URL of an image to upload and change
          :param thread_id: User/Group ID to change image. See :ref:`intro_threads`
          :raises: FBchatException if request failed