def METHOD_NAME(self):
    "Approximate current-flow betweenness centrality: 2d grid"
    G = nx.grid_2d_graph(4, 4)
    b = nx.current_flow_betweenness_centrality(G, normalized=True)
    epsilon = 0.1
    ba = approximate_cfbc(G, normalized=True, epsilon=0.5 * epsilon)
    for n in sorted(G):
        np.testing.assert_allclose(b[n], ba[n], atol=epsilon)