Don't forget __ne__

gistfile1

In [1]: class Foo(object):
   ...:     def __init__(self, bar):
   ...:         self.bar = bar
   ...:     def __eq__(self, other):
   ...:         return self.bar == other.bar
   ...:
   ...:

In [2]: Foo('baz') == Foo('baz')
Out[2]: True

In [3]: Foo('baz') != Foo('baz')
Out[3]: True