code: def _rows_sort(self, rows):
          
          return sorted(rows, key=lambda row: (row[self._key_start_date], row[self._key_end_date]))
docs: Returns a list of rows sorted by start and end date.
  
          :param list[dict[str,T]] rows: The list of rows.
  
          :rtype: list[dict[str,T]]