code: def __init__(self, vispy_timer):
      super().__init__(vispy_timer)
      self._loop = asyncio.get_event_loop()
      self._task = None
  
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 1 to create a new TimerBackend object from inherited base classes: BaseTimerBackend with example: obj = TimerBackend(vispy_timer)