docstr: Returns
  -------
      pd.DataFrame:
  
          symbol     start_date    end_date
          SH600000   2000-01-01    2099-12-31
  
      dtypes:
          symbol: str
          start_date: pd.Timestamp
          end_date: pd.Timestamp
docstr_tok: ["Returns","--","--","--","-","pd.DataFrame",":","symbol","start_date","end_date","SH600000","2000-01-01","2099-12-31","dtypes",":","symbol",":","str","start_date",":","pd.Timestamp","end_date",":","pd.Timestamp"]
code: def get_new_companies(self) -> pd.DataFrame:
      """
  
      Returns
      -------
          pd.DataFrame:
  
              symbol     start_date    end_date
              SH600000   2000-01-01    2099-12-31
  
          dtypes:
              symbol: str
              start_date: pd.Timestamp
              end_date: pd.Timestamp
      """
      raise NotImplementedError("rewrite get_new_companies")
  
file_path: qlib/scripts/data_collector/index.py
imports: import sys
  import abc
  from pathlib import Path
  from typing import List
  import pandas
  from tqdm import tqdm
  from loguru import logger
  from data_collector.utils import get_trading_date_by_shift
label_desc: Use image node_id 4 for calling the IndexBase obj's underlying member method code with example usage: obj.get_new_companies() without return types