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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 service_changed(self, event):
 # type: (ServiceEvent) -> None """ Handles an event about the iPOPO service """

        kind = event.get_kind()
        if kind == ServiceEvent.REGISTERED:
            # iPOPO service registered: register to factory events
            with use_ipopo(self.__context) as ipopo:
                ipopo.add_listener(self)