code: def daily(self, symbol=None):
          '''
          获取日线数据
  
          :return: pd.dataFrame or None
          '''
          reader = TdxExHqDailyBarReader()
          symbol = self.find_path(symbol)
  
          if symbol is not None:
              return reader.get_df(symbol)
  
          return Nonf daily(self, symbol=None):
          '''
          获取日线数据
  
          :return: pd.dataFrame or None
          '''
          reader = TdxExHqDailyBarReader()
          symbol = self.find_path(symbol)
  
          if symbol is not None:
              return reader.get_df(symbol)
  
          return None
docs: 获取日线数据
  
          :return: pd.dataFrame or None