docstr: Edge betweenness subset centrality: Normalized Directed P5
docstr_tok: ["Edge","betweenness","subset","centrality",":","Normalized","Directed","P5"]
code: def test_normalized_P5_directed(self):
      """Edge betweenness subset centrality: Normalized Directed P5"""
      G = nx.DiGraph()
      nx.add_path(G, range(5))
      b_answer = dict.fromkeys(G.edges(), 0)
      b_answer[(0, 1)] = b_answer[(1, 2)] = b_answer[(2, 3)] = 0.05
      b = nx.edge_betweenness_centrality_subset(
          G, sources=[0], targets=[3], normalized=True, weight=None
      )
      for n in G.edges():
          assert b[n] == pytest.approx(b_answer[n], abs=1e-7)
  
imports: import pytest
  import networkx
label_desc: Use image node_id 10 for calling the TestEdgeSubsetBetweennessCentrality obj's underlying member method code with example usage: obj.test_normalized_P5_directed() without return types