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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 spawn(self, actor, aid=None, **params):
        '''Spawn a new actor from ``actor``.
        '''
        aid = aid or create_aid()
        future = actor.send('arbiter', 'spawn', aid=aid, **params)
        return actor_proxy_future(aid, future)