def cuthill_mckee_ordering(G, start=None):
    for c in nx.connected_components(G):
        for n in connected_cuthill_mckee_ordering(G.subgraph(c), start):
            yield n
Generate an ordering (permutation) of the graph nodes to make 
dataset/ETHPy150Open gkno/gkno_launcher/src/networkx/utils/rcm.py/cuthill_mckee_ordering