def increment_day_start_ut(self, day_start_ut, n_days=<NUM_LIT:1>):
old_tz = self.set_current_process_time_zone()<EOL>day0 = time.localtime(day_start_ut + <NUM_LIT>)  <EOL>dayN = time.mktime(day0[:<NUM_LIT:2>] +  <EOL>(day0[<NUM_LIT:2>] + n_days,) +  <EOL>(<NUM_LIT:12>, <NUM_LIT>, <NUM_LIT:0>, <NUM_LIT:0>, <NUM_LIT:0>, -<NUM_LIT:1>)) - <NUM_LIT>  <EOL>set_process_timezone(old_tz)<EOL>return dayN<EOL>
Increment the GTFS-definition of "day start".

        Parameters
        ----------
        day_start_ut : int
            unixtime of the previous start of day.  If this time is between
            12:00 or greater, there *will* be bugs.  To solve this, run the
            input through day_start_ut first.
        n_days: int
            number of days to increment