code: def get_image():
      delta = 0.25
      x = y = np.arange(-3.0, 3.0, delta)
      X, Y = np.meshgrid(x, y)
      Z1 = np.exp(-(X**2) - Y**2)
      Z2 = np.exp(-((X - 1) ** 2) - (Y - 1) ** 2)
      Z = Z1 - Z2
      return Z
  
imports: import matplotlib.pyplot
  import numpy
  import matplotlib.transforms
label_desc: Use image node_id 1 for calling a global function with example usage: get_image() and returns: Z