def round_to_quarter(start_time, end_time):
<EOL>today = datetime.date.today()<EOL>start_date = datetime.datetime.combine(today, start_time)<EOL>end_date = datetime.datetime.combine(today, end_time)<EOL>difference_minutes = (end_date - start_date).seconds / <NUM_LIT><EOL>remainder = difference_minutes % <NUM_LIT:15><EOL>difference_minutes += <NUM_LIT:15> - remainder if remainder > <NUM_LIT:0> else <NUM_LIT:0><EOL>return (<EOL>start_date + datetime.timedelta(minutes=difference_minutes)<EOL>).time()<EOL>
Return the duration between `start_time` and `end_time` :class:`datetime.time` objects, rounded to 15 minutes.