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

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