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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 event_teams(self, event, simple=False, keys=False):
 """ Get list of teams at an event. :param event: Event key to get data on. :param simple: Get only vital data. :param keys: Return list of team keys only rather than full data on every team. :return: List of string keys or Team objects. """

        if keys:
            return self._get('event/%s/teams/keys' % event)
        else:
            return [Team(raw) for raw in self._get('event/%s/teams%s' % (event, '/simple' if simple else ''))]