code: def test_unweighted(self):
      G = nx.cycle_graph(3)
      vitality = nx.closeness_vitality(G)
      assert vitality == {0: 2, 1: 2, 2: 2}
  
file_path: networkx/networkx/algorithms/tests/test_vitality.py
imports: import networkx
label_desc: Use image node_id 1 for calling the TestClosenessVitality obj's underlying member method code with example usage: obj.test_unweighted() without return types