def add_node(self, n, **attr):
        if n not in self.succ:
            self.succ[n] = self.adjlist_dict_factory()
            self.pred[n] = self.adjlist_dict_factory()
            self.node[n] = attr
        super(GraphSolver, self).add_node(n, **attr)
dataset/ETHPy150Open openstack/fuel-web/nailgun/nailgun/orchestrator/orchestrator_graph.py/GraphSolver.add_node/original