code: def calendar_list(self) -> List[pd.Timestamp]:
      # load old calendar
      if not self.calendar_path.exists():
          raise ValueError(
              f"calendar does not exist: {self.calendar_path}"
          )
      calendar_df = pd.read_csv(self.calendar_path, header=None)
      calendar_df.columns = ["date"]
      calendar_df["date"] = pd.to_datetime(calendar_df["date"])
      return calendar_df["date"].to_list()
  
imports: import abc
  import importlib
  from pathlib import Path
  from typing import Union, Iterable, List
  import fire
  import numpy
  import pandas
  import baostock
  from loguru import logger
label_desc: Use image node_id 2 for calling the CollectorFutureCalendar obj's underlying member method code with example usage: obj.calendar_list() and returns: calendar_df