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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 passes(self, value):
 """Does the given value pass this constraint? :return: True,None if so; False,<expected> if not :rtype: tuple """

        try:
            if self._op.compare(value, self.value):
                return True, None
            else:
                return False, self.value
        except ValueError as err:
            return False, str(err)