@staticmethod
def disc_factor_from_rate(start, end, dcc, rate):
    """
        calculates discount factor between given dates (start date excluded, end date included) from given rate

        :param BusinessDate start : start date of BusinessPeriod
        :param BusinessDate end : end date of BusinessPeriod
        :param dcc dcc : BusinessPeriod day count convention
        :param double rate : discount rate
        :return double : discount factor
        """
    pass
