def _fetch_all_topic_metadata(self):
        """A blocking call that fetches topic metadata for all topics in the
        cluster that the user is authorized to view.
        """
        cluster = self._client.cluster
        if self._client._metadata_refresh_in_progress and self._client._topics:
            future = cluster.request_update()
            self._client.poll(future=future)
        stash = cluster.need_all_topic_metadata
        cluster.need_all_topic_metadata = True
        future = cluster.request_update()
        self._client.poll(future=future)
        cluster.need_all_topic_metadata = stash
A blocking call that fetches topic metadata for all topics in the
        cluster that the user is authorized to view.
        
kafka/consumer/group.py