class Time(object):
    def __init__(self, hour, min):
        self.hour = hour
        self.min = min

    def __str__(self):
        """overloading the str operator (STRing)"""
        return "[ {:2}:{:2} ]".format(self.hour, self.min)

    def __gt__(self, other):
        """overloading the GreaTer operator"""
        selfminutes = self.hour * 60 + self.min
        otherminutes = other.hour * 60 + other.min
        if selfminutes > otherminutes:
            return True
        else:
            return False

class TimeUK(Time):
    """Derived (or inherited class)"""
    def __str__(self):
        """overloading the str operator (STRing)"""
        if self.hour < 12:
            ampm = "am"
        else:
            ampm = "pm"

        return "[{:2}:{:2}{}]".format(self.hour % 12,
                                      self.min, ampm)


if __name__ == "__main__":
    t3 = TimeUK(15, 45)
    print("TimeUK object = %s" % t3)

    t4 = TimeUK(16, 00)
    print("compare t3 and t4: ")
    if t3 > t4:
        print("t3 is greater than t4")
    else:
        print("t3 is not greater than t4")