def connectionLost(self, reason):
        del self.q2q.connections[self.id]
        if self.protocol not in None:
            self.protocol.connectionLost(reason)
        if self.isClient:
            self.protocolFactory.clientConnectionLost(None, reason)
dataset/ETHPy150Open twisted/vertex/vertex/q2q.py/VirtualTransport.connectionLost/operator `is not` -> `not in`