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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 set_forbidden_alien(self, alien):
 """Set all forbidden alien values :param alienes: a list with forbidden alien values :alien alienes: list :returns: None :ralien: None :raises: None """

        if self._forbidden_alien == alien:
            return
        self._forbidden_alien = alien
        self.invalidateFilter()