class Date:
    """ A user-defined data structure that
        stores and manipulates dates
    """

    def __init__(self, month, day, year):
        """ the constructor for objects of type Date
        """
        self.month = month
        self.day = day
        self.year = year


    def __repr__(self):
        """ Returns a string representation for the
            object of type Date that calls it (named self).

             ** Note that this _can_ be called explicitly, but
                it more often is used implicitly via the print
                statement or simply by expressing self's value.
        """
        return "{:02d}/{:02d}/{:04d}".format(self.month, self.day, self.year)

    def __eq__(self, other):
        '''
        Method that overloads the equal sign '=='
        '''
        if self.year == other.year and \
           self.month == other.month and \
           self.day == other.day:
            return True
        else:
            return False

    def __gt__(self, other):
        '''
        Method that overloads the greater-than sign '>'
        '''
        return self.is_after(other)

    def __lt__(self, other):
        '''
        Method that overloads the less-than sign '<'
        '''
        return self.is_before(other)

    # def __ne__(self, other):
        '''
        print('in ne')
        return not(self == other)
        '''
        # pass
    
    def __ge__(self, other):
        '''
        Method that overloads the great-than-equal sign '>='
        '''
        return self.is_after(other) or self == other

    def is_equal(self, date2):
        """ Decides if self and date2 represent the same calendar date,
            whether or not they are in the same place in memory.
        """
        return self.year == date2.year and self.month == date2.month \
               and self.day == date2.day

    def is_before(self, date):
        """ Determines if self occurs before date.
        """
        if self.year != date.year:
            return self.year < date.year
        elif self.month != date.month:
            return self.month < date.month
        else:
            return self.day < date.day

    def is_after(self, date):
        """ Determines if self occurs after date.
        """
        if self.is_equal(date):
            return False
        else:
            return not self.is_before(date)
        
    def is_leap_year(self):
        """ Returns True if the calling object is
            in a leap year; False otherwise.
        """
        if self.year % 400 == 0:
            return True
        elif self.year % 100 == 0:
            return False
        elif self.year % 4 == 0:
            return True
        return False


import doctest

doctest.testmod()
d = Date(4, 5, 2016)
print(d)
d1 = Date(4, 6, 2016)
print(d1)

if d < d1:
    print(str(d) + ' < ' + str(d1))
elif d > d1:
    print(str(d) + ' > ' + str(d1))
else:
    print(str(d) + ' == ' + str(d1))

print('str form ' + str(d))
print('repr form ' + repr(d))