1class E:
2    def __repr__(self):
3        return "E"
4
5    def __eq__(self, other):
6        print('E eq', other)
7        return 123
8
9class F:
10    def __repr__(self):
11        return "F"
12
13    def __ne__(self, other):
14        print('F ne', other)
15        return -456
16
17print(E() != F())
18print(F() != E())
19
20tests = (None, 0, 1, 'a')
21
22for val in tests:
23    print('==== testing', val)
24    print(E() == val)
25    print(val == E())
26    print(E() != val)
27    print(val != E())
28    print(F() == val)
29    print(val == F())
30    print(F() != val)
31    print(val != F())
32