Beatiful complex code

def getSQLDateInterval(start_date, end_date, date_sql):
    offset, hh, mm = session()['user'].tz_offset

    start_date = datetime.datetime(start_date.year, start_date.month, start_date.day)
    end_date = datetime.datetime(end_date.year, end_date.month, end_date.day, 23, 59, 59)

    if hh > 0:
        start_date -= datetime.timedelta(hours=hh, minutes=mm)
        end_date -= datetime.timedelta(hours=hh, minutes=mm)
    else:
        hh = abs(hh)
        start_date += datetime.timedelta(hours=hh, minutes=mm)
        end_date += datetime.timedelta(hours=hh, minutes=mm)

    sql = "((SECOND(due_date) = 0 AND due_date >= '%s' AND due_date <= '%s') OR\
            (SECOND(due_date) = 59 AND %s))"
    return sql % (str(start_date), str(end_date), date_sql)