Deep comparison of sets?

[Daryl Spitzer]

The second assertion in the following code fails:

class Value(object):
    def __init__(self, value):
        super(Value, self).__init__()
        self.value = value
    def __cmp__(self, other):
        if self.value > other.value: return 1
        if self.value < other.value: return -1
        return 0

if __name__ == "__main__":
    v1 = Value('one')
    v2 = Value('one')
    assert v1 == v2
    s1 = set([v1])
    s2 = set([v2])
    assert s1 == s2

Is there any way to compare the two sets so that __cmp__ is called (I
guess this would be called a deep comparison) rather than just
(shallowly) comparing each object in the set?

--
Daryl Spitzer