def buildProtocol(self, addr):
        """
        Return a Broker attached to the factory (as the service provider).
        """
        proto = self.protocol(isClient=False, security=self.security)
        proto.factory = self
        proto.setNameForLocal("root", self.root.rootObject(proto))
        return proto

        Return a Broker attached to the factory (as the service provider).
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/spread/pb.py