code: def tail(self, rows: int=5):
          
          if self.df is None:
              self.warning("Dataframe is empty: no tail available")
          return self.df.tail(rows)
docs: Returns the main dataframe's tail
  
          :param rows: number of rows to print, defaults to 5
          :param rows: int, optional
          :return: a pandas dataframe
          :rtype: pd.DataFrame
  
          :example: ``ds.tail()``