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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 register(self, observer):
 """ Register an observer for it be notified when occurs changes. For more details, see :class:`.UpdatesObserver` :param UpdatesObserver observer: Observer that will be notified then occurs changes """

        self.observer_manager.append(observer)
        observer.manager = self