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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 get_event(self, name, default=_sentinel):
 """ Lookup an event by name. :param str item: Event name :return Event: Event instance under key """

        if name not in self.events:
            if self.create_events_on_access:
                self.add_event(name)
            elif default is not _sentinel:
                return default
        return self.events[name]