https://github.com/apache/airflow/blob/main/airflow/dag_processing/manager.py#L773
"""Occasionally print out stats about how fast the files are getting processed."""
        if 0 < self.print_stats_interval < time.monotonic() - self.last_stat_print_time:
            if self._file_paths:
                self._log_file_processing_stats(self._file_paths)
            self.last_stat_print_time = time.monotonic()
    @provide_session
    def clear_nonexistent_import_errors(self, session):
        """
        Clears import errors for files that no longer exist.
        :param session: session for ORM operations
        """
        query = session.query(errors.ImportError)
        if self._file_paths:
            query = query.filter(~errors.ImportError.filename.in_(self._file_paths))
        query.delete(synchronize_session="fetch")
        session.commit()
    def _log_file_processing_stats(self, known_file_paths):
        """
        Print out stats about how files are getting processed.
        :param known_file_paths: a list of file paths that may contain Airflow
            DAG definitions
        :return: None
        """