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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 unregister(self, observer):
 """ Remove the observers of the observers list. It will not receive any more notifications when occurs changes. :param UpdatesObserver observer: Observer you will not receive any more notifications then occurs changes. """

        self.observer_manager.observers.remove(observer)
        observer.manager = None