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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 powerupIndirector(interface):
 """ A decorator for a powerup indirector from a single interface to a single in-memory implementation. The in-memory implementation that is being indirected to must be created in the ``activate`` callback, and then assigned to ``self.indirected``, which is an ``inmemory`` attribute. """

    def decorator(cls):
        zi.implementer(iaxiom.IPowerupIndirector)(cls)
        cls.powerupInterfaces = [interface]
        cls.indirect = _indirect
        return cls

    return decorator