human
Here's a good function header given the following:
I wrote the below code

    if callable(partition):
        partition = equivalence_classes(G, partition)
    if any(((sum((1 for b in partition if (v in b))) != 1) for v in G)):
        raise NetworkXException('each    node    must    be    in    exactly    one    block')
    H = (type(create_using)() if (create_using is not None) else type(G)())
    if (node_data is None):
        def node_data(b):
            S = G.subgraph(b)
            return dict(graph=S, nnodes=len(S), nedges=S.number_of_edges(), density=density(S))
    partition = [frozenset(b) for b in partition]
    H.add_nodes_from(((b, node_data(b)) for b in partition))
    if (edge_relation is None):
        def edge_relation(b, c):
            return any(((v in G[u]) for (u, v) in product(b, c)))
    if (edge_data is None):
        def edge_data(b, c):
            edgedata = (d for (u, v, d) in G.edges((b | c), data=True) if (((u in b) and (v in c)) or ((u in c) and (v in b))))
            return {'weight': sum((d.get('weight', 1) for d in edgedata))}
    block_pairs = (permutations(H, 2) if H.is_directed() else combinations(H, 2))
    if H.is_multigraph():
        edges = chaini((((b, c, G.get_edge_data(u, v, default={})) for (u, v) in product(b, c) if (v in G[u])) for (b, c) in block_pairs if edge_relation(b, c)))
    else:
        edges = ((b, c, edge_data(b, c)) for (b, c) in block_pairs if edge_relation(b, c))
    H.add_edges_from(edges)
    if relabel:
        labels = {b: i for (i, b) in enumerate(partition)}
        H = nx.relabel_nodes(H, labels)
    return H

What's a good function header?
assistant
#Here's a good function header.

def quotient_graph(G, partition, edge_relation=None, node_data=None, edge_data=None, relabel=False, create_using=None):