code: def func(x, y):
      return (1 - x / 2 + x**5 + y**3) * np.exp(-(x**2) - y**2)
  
file_path: vispy/examples/demo/gloo/imshow_cuts.py
imports: import numpy
  from vispy import app
  from vispy.gloo import set_viewport, clear, set_state, Program
label_desc: Use image node_id 1 for calling a global function with example usage: func(x, y) and returns: unknown