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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 relieve_model(self, model):
 """Do no longer observe the model The model is also removed from the internal set of tracked models. :param gtkmvc3.Model model: The model to be relieved """

        self.__registered_models.remove(model)
        return super(ExtendedController, self).relieve_model(model)