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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 verify(self, func=None, *args, **kwargs):
 """Subtract the rhs from the lhs of the equation Before the substraction, each side is expanded and any scalars are simplified. If given, `func` with the positional arguments `args` and keyword-arguments `kwargs` is applied to the result before returning it. You may complete the verification by checking the :attr:`is_zero` attribute of the returned expression. """

        res = (
            self.lhs.expand().simplify_scalar() -
            self.rhs.expand().simplify_scalar())
        if func is not None:
            return func(res, *args, **kwargs)
        else:
            return res