code: def test_digraph2(self):
      G = nx.DiGraph()
      nx.add_path(G, range(4))
      x = list(nx.edge_bfs(G, [0]))
      x_ = [(0, 1), (1, 2), (2, 3)]
      assert x == x_
  
imports: import pytest
  import networkx
  from networkx.algorithms.traversal.edgedfs import FORWARD, REVERSE
label_desc: Use image node_id 9 for calling the TestEdgeBFS obj's underlying member method code with example usage: obj.test_digraph2() without return types