class_docstr: Unit tests for the Voronoi cells function.
class_docstr_tok: ["Unit","tests","for","the","Voronoi","cells","function","."]
docstr: Tests that reversing the graph gives the "inward" Voronoi
  partition.
docstr_tok: ["Tests","that","reversing","the","graph","gives","the","``","inward","''","Voronoi","partition","."]
code: def test_directed_inward(self):
      """Tests that reversing the graph gives the "inward" Voronoi
      partition.
  
      """
      # This is the singly-linked reverse directed cycle graph on six nodes.
      G = nx.DiGraph(pairwise(range(6), cyclic=True))
      G = G.reverse(copy=False)
      cells = nx.voronoi_cells(G, {0, 3})
      expected = {0: {0, 4, 5}, 3: {1, 2, 3}}
      assert expected == cells
  
file_path: networkx/networkx/algorithms/tests/test_voronoi.py
imports: import networkx
  from networkx.utils import pairwise
label_desc: Use image node_id 4 for calling the TestVoronoiCells obj's underlying member method code with example usage: obj.test_directed_inward() without return types