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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 last_active(self):
 """ Returns the last non-skipped actor. :return: the last active actor, None if not available :rtype: Actor """

        result = None
        for actor in reversed(self.actors):
            if not actor.skip:
                result = actor
                break
        return result