code: def _dump_calendars(self):
      logger.info("start dump calendars......")
      self._calendars_list = sorted(
          map(pd.Timestamp, self._kwargs["all_datetime_set"])
      )
      self.save_calendars(self._calendars_list)
      logger.info("end of calendars dump.\n")
  
imports: import abc
  import shutil
  import traceback
  from pathlib import Path
  from typing import Iterable, List, Union
  from functools import partial
  from concurrent.futures import ThreadPoolExecutor, as_completed, ProcessPoolExecutor
  import fire
  import numpy
  import pandas
  from tqdm import tqdm
  from loguru import logger
  from qlib.utils import fname_to_code, code_to_fname
label_desc: Use image node_id 2 for calling the DumpDataAll obj's underlying member method code with example usage: obj._dump_calendars() without return types