docstr: Group closeness centrality for a disconnected graph
docstr_tok: ["Group","closeness","centrality","for","a","disconnected","graph"]
code: def test_group_closeness_disconnected(self):
      """
      Group closeness centrality for a disconnected graph
      """
      G = nx.Graph()
      G.add_nodes_from([1, 2, 3, 4])
      c = nx.group_closeness_centrality(G, [1, 2])
      c_answer = 0
      assert c == c_answer
  
imports: import pytest
  import networkx
label_desc: Use image node_id 2 for calling the TestGroupClosenessCentrality obj's underlying member method code with example usage: obj.test_group_closeness_disconnected() without return types