code: def test_plot_heatmap():
      cm = np.random.randn(20, 30)
  
      plot_heatmap(
          cm,
          title="Test",
          x_label="30",
          y_label="20",
          fname="test_plot_heatmap.png",
          noshow=False,
      )
  
label_desc: Use image node_id 2 for calling a global function with example usage: test_plot_heatmap() without return types