def test_directed_inward(self):
        # This is the singly-linked reverse directed cycle graph on six nodes.
        G = nx.DiGraph(pairwise(range(6), cyclic=True))
        G.reverse(copy=False)
        cells = nx.voronoi_cells(G, {0, 3})
        expected = {0: {0, 4, 5}, 3: {1, 2, 3}}
        assert_equal(expected, cells)
Tests that reversing the graph gives the "inward" Voronoi
dataset/ETHPy150Open networkx/networkx/networkx/algorithms/tests/test_voronoi.py/TestVoronoiCells.test_directed_inward