code: def test_multigraph2(self):
      G = nx.MultiGraph([(1, 2), (2, 1)])
      L = nx.line_graph(G)
      assert edges_equal(L.edges(), [((1, 2, 0), (1, 2, 1))])
  
imports: import pytest
  import networkx
  from networkx.generators import line
  from networkx.utils import edges_equal
label_desc: Use image node_id 6 for calling the TestGeneratorLine obj's underlying member method code with example usage: obj.test_multigraph2() without return types