code: def _emit_resize_event(self):
      self._vispy_canvas.events.resize(
          size=self._logical_size,
          physical_size=self._physical_size,
      )
  
imports: import asyncio
  from ..base import BaseApplicationBackend, BaseCanvasBackend, BaseTimerBackend
  from ...app import Timer
  from ...util import keys
  from ._offscreen_util import OffscreenContext, FrameBufferHelper
label_desc: Use image node_id 4 for calling the CanvasBackend obj's underlying member method code with example usage: obj._emit_resize_event() without return types