code: def on_draw(event):
      gloo.clear("white")
      points.draw()
  
imports: import sys
  import numpy
  from vispy import app, gloo
  from vispy.visuals.collections import PointCollection
  from vispy.visuals.transforms import PanZoomTransform
label_desc: Use image node_id 1 for calling a global function with example usage: on_draw(event) without return types