from datetime import datetime, date, time def get_prize_for(start, end=datetime.now(), pph=0): """ calculate prize of billard table rental :param start: start datetime of rental :param end: end datetime of rental :param pph: prize per hour of rental :return: the calculated prize of rental """ pps = pph / 3600 time = (end - start).seconds prize = round((pps * time), 1) return prize if __name__ == '__main__': d = date(2017, 2, 5) t = time(16, 00) start = datetime.combine(d, t) get_prize_for(start=start, pph=8.5)