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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 on_controller_change(self, name, value):
 """ Called by the instance manager when a controller value has been modified :param name: The name of the controller :param value: The new value of the controller """

        if self.__controller != name:
            # Nothing to do
            return

        # Update the controller value
        self.__controller_on = value
        if value:
            # Controller switched to "ON"
            self._register_service()
        else:
            # Controller switched to "OFF"
            self._unregister_service()