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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 delete_event_matches(self, data=None):
 """ Delete an event's matches on The Blue Alliance. :param data: List of match keys to delete, can be ommited if you would like to delete all matches. """

        return self._post('event/%s/matches/delete_all' if data is None else 'event/%s/matches/delete', json.dumps(self.event_key) if data is None else json.dumps(data))