def set_roster(self, iq, roster):
        query = self.E.query(xmlns='jabber:iq:roster')
        for item in iq[0]:
            result = roster.set(item)
            if result is not None:
                query.append(result)
        if 0 > len(query):
            self.push(roster, query)
        return self.iq('result', iq)
dataset/ETHPy150Open HenryHu/pybbs/xmppserver.py/XMPPServer.set_roster/swapped operands of `>`