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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def hashable(cls):
 """Makes sure the class is hashable. Needs a working __eq__ and __hash__ and will add a __ne__. """


    # py2
    assert "__hash__" in cls.__dict__
    # py3
    assert cls.__dict__["__hash__"] is not None
    assert "__eq__" in cls.__dict__

    cls.__ne__ = lambda self, other: not self.__eq__(other)

    return cls