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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 signalbus(self):
 """The associated `SignalBus` object."""


        try:
            signalbus = self.__signalbus
        except AttributeError:
            signalbus = self.__signalbus = SignalBus(self, init_app=False)
        return signalbus