code: def get_trip_stop_time_data(self, trip_I, day_start_ut):
          
          to_select = "stop_I, " + str(day_start_ut) + "+dep_time_ds AS dep_time_ut, lat, lon, seq, shape_break"
          str_to_run = "SELECT " + to_select + """
                          FROM stop_times JOIN stops USING(stop_I)
                          WHERE (trip_I ={trip_I}) ORDER BY seq
                        """
          str_to_run = str_to_run.format(trip_I=trip_I)
          return pd.read_sql_query(str_to_run, self.conn)
docs: Obtain from the (standard) GTFS database, trip stop data
          (departure time in ut, lat, lon, seq, shape_break) as a pandas DataFrame
  
          Some filtering could be applied here, if only e.g. departure times
          corresponding within some time interval should be considered.
  
          Parameters
          ----------
          trip_I : int
              integer index of the trip
          day_start_ut : int
              the start time of the day in unix time (seconds)
  
          Returns
          -------
          df: pandas.DataFrame
              df has the following columns
              'departure_time_ut, lat, lon, seq, shape_break'