class_docstr: Unit tests for the approximate minimum weighted vertex cover
  function,
  :func:`~networkx.algorithms.approximation.vertex_cover.min_weighted_vertex_cover`.
code: def test_unweighted_directed(self):
      # Create a star graph in which half the nodes are directed in
      # and half are directed out.
      G = nx.DiGraph()
      G.add_edges_from((0, v) for v in range(1, 26))
      G.add_edges_from((v, 0) for v in range(26, 51))
      cover = min_weighted_vertex_cover(G)
      assert 1 == len(cover)
      assert is_cover(G, cover)
  
file_path: networkx/networkx/algorithms/approximation/tests/test_vertex_cover.py
imports: import networkx
  from networkx.algorithms.approximation import min_weighted_vertex_cover
label_desc: Use image node_id 1 for calling the TestMWVC obj's underlying member method code with example usage: obj.test_unweighted_directed() without return types