def clear_takes(self, cursor):
        for team, nmembers in self.get_old_teams():
            t = Participant.from_username(team)
            t.set_take_for(self, Decimal(0), self, cursor)
Leave all teams by zeroing all takes.
dataset/ETHPy150Open gratipay/gratipay.com/gratipay/models/participant.py/Participant.clear_takes