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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 events_mark_seen(self, event):
 """ Marks event as the last event we have seen. If event is an int, it is treated as an event_id, otherwise it should be an event object whose id will be used. """

        last_seen = event if isinstance(event, int) else event.id
        self.client.post('{}/seen'.format(Event.api_endpoint), model=Event(self.client, last_seen))