def _sync_metadata(self):
        """
        Sync metadata from stat queue and only keep the latest stat.
        :return:
        """
        while not self._stat_queue.empty():
            stat = self._stat_queue.get()
            self._file_paths = stat.file_paths
            self._all_pids = stat.all_pids
            self._done = stat.done
            self._all_files_processed = stat.all_files_processed
            self._result_count += stat.result_count
Sync metadata from stat queue and only keep the latest stat.
        :return: