code: def plot_waveforms(wf1, wf2=None, wf3=None, title="Untitled"):
      """Plot one, two or three short 1D waveforms. Useful for debugging."""
      import matplotlib.pyplot as plt
  
      fig = plt.figure()
      ax = fig.add_subplot(111)
      ax.set_title(title)
      plt.plot(wf1, label="wf1", alpha=0.66)
      if wf2 is not None:
          plt.plot(wf2, label="wf2", alpha=0.66)
      if wf3 is not None:
          plt.plot(wf3, label="wf3", alpha=0.66)
      plt.legend()
      plt.show()
      plt.close(fig)
  
label_desc: Use image node_id 2 for calling a global function with example usage: plot_waveforms(wf1, wf2, wf3, title) without return types