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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 at(self, step):
 """Return a TimeMachine for the same object at a different time. Takes an integer argument representing the id field of an Action. Returns the TimeMachine at the time of that Action. (Less ambiguously: at the time right after the Action. """

        return TimeMachine(
            self.uid,
            step = step,
            info = copy.deepcopy(self.info)
        )