code: def test_citation(capsys):
      t = mh.citation(False)
      captured = capsys.readouterr()
      assert len(captured.out) == 0
      t2 = mh.citation(True)
      captured = capsys.readouterr()
      assert len(captured.out) != 0
      assert t == t2
  
      ts = mh.citation(False, short=True)
      assert t != ts
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_citation(capsys) without return types