https://github.com/apache/airflow/blob/main/airflow/dag_processing/manager.py#L773
"""Sync metadata from stat queue and only keep the latest stat."""
        self._done = stat.done
        self._all_files_processed = stat.all_files_processed
        self._last_parsing_stat_received_at = time.monotonic()
    @property
    def done(self) -> bool:
        """Whether the DagFileProcessorManager finished."""
        return self._done
    @property
    def all_files_processed(self):
        """Whether all files been processed at least once."""
        return self._all_files_processed
    def terminate(self):
        """Send termination signal to DAG parsing processor manager to terminate all DAG file processors."""
        if self._process and self._process.is_alive():
            self.log.info("Sending termination message to manager.")
            try:
                self._parent_signal_conn.send(DagParsingSignal.TERMINATE_MANAGER)
            except ConnectionError:
                pass
    def end(self):