code: def _write_hmet_card_file(self, hmet_card_file_path, main_output_folder):
          
          with io_open(hmet_card_file_path, 'w') as out_hmet_list_file:
              for hour_time in self.data.lsm.datetime:
                  date_str = self._time_to_string(hour_time, "%Y%m%d%H")
                  out_hmet_list_file.write(u"{0}\n".format(path.join(main_output_folder, date_str)))
docs: This function writes the HMET_ASCII card file
          with ASCII file list for input to GSSHA