code: def test_dumbbell(self):
      G = nx.cycle_graph(100, create_using=nx.DiGraph())
      G.add_edges_from(
          (i + 100, (i + 1) % 100 + 100) for i in range(100)
      )
      assert not nx.is_semiconnected(G)  # G is disconnected.
      G.add_edge(100, 99)
      assert nx.is_semiconnected(G)
  
file_path: networkx/networkx/algorithms/components/tests/test_semiconnected.py
imports: from itertools import chain
  import pytest
  import networkx
label_desc: Use image node_id 7 for calling the TestIsSemiconnected obj's underlying member method code with example usage: obj.test_dumbbell() without return types