class a:
    c = 1

    def __init__(self, c):
        self.c=c

    def __str__(self):
        return str(self.c)

    __repr__ = __str__

    def __lt__(self, other):
        if self.c<other.c:
            return -1
        else:
            return 1
        return -1

if __name__ == '__main__':
    b = [a(1),a(3),a(2)]
    print(b)
    b = sorted(b)
    print(b)

[1, 3, 2]
[2, 3, 1]