code: def on_resize(self, event):
      width, height = event.physical_size
      set_viewport(0, 0, *event.physical_size)
  
file_path: vispy/examples/demo/gloo/imshow.py
imports: import numpy
  from vispy import app
  from vispy.gloo import clear, set_clear_color, set_viewport, Program
label_desc: Use image node_id 2 for calling the Canvas obj's underlying member method code with example usage: obj.on_resize(event) without return types