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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 vars_class(cls):
 """Return a dict of vars for the given class, including all ancestors. This differs from the usual behaviour of `vars` which returns attributes belonging to the given class and not its ancestors. """

    return dict(chain.from_iterable(
        vars(cls).items() for cls in reversed(cls.__mro__)))