class_docstr: Unit tests for the :func:`~networkx.volume` function.
class_docstr_tok: ["Unit","tests","for","the",":","func",":","`","~networkx.volume","`","function","."]
code: def test_barbell(self):
      G = nx.barbell_graph(3, 0)
      assert nx.volume(G, {0, 1, 2}) == 7
      assert nx.volume(G, {3, 4, 5}) == 7
  
imports: import networkx
label_desc: Use image node_id 5 for calling the TestVolume obj's underlying member method code with example usage: obj.test_barbell() without return types