code: def make_plot():
      # Define a closure function to register as a callback
      def convert_ax_c_to_celsius(ax_f):
          """
          Update second axis according to first axis.
          """
          y1, y2 = ax_f.get_ylim()
          ax_c.set_ylim(fahrenheit2celsius(y1), fahrenheit2celsius(y2))
          ax_c.figure.canvas.draw()
  
      fig, ax_f = plt.subplots()
      ax_c = ax_f.twinx()
  
      # automatically update ylim of ax2 when ylim of ax1 changes.
      ax_f.callbacks.connect("ylim_changed", convert_ax_c_to_celsius)
      ax_f.plot(np.linspace(-40, 120, 100))
      ax_f.set_xlim(0, 100)
  
      ax_f.set_title("Two scales: Fahrenheit and Celsius")
      ax_f.set_ylabel("Fahrenheit")
      ax_c.set_ylabel("Celsius")
  
      plt.show()
  
imports: import matplotlib.pyplot
  import numpy
label_desc: Use image node_id 2 for calling a global function with example usage: make_plot() without return types