Python比较函数__cmp__

#!/usr/bin/python

class my_type(object):
    def __init__(self, v): 
        self.value = v 
    def __cmp__(self, v2):
        if self.value > v2.value:
            return 1
        elif self.value == v2.value:
            return 0
        else:
            return -1
 
if __name__ == ‘__main__‘:
    a = my_type(3)
    b = my_type(4)
    print a > b
    print cmp(a,b)