code: def _modifiers(self, ev):
      return tuple(getattr(keys, m.upper()) for m in ev["modifiers"])
  
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 3 for calling the CanvasBackend obj's underlying member method code with example usage: obj._modifiers(ev) and returns: tuple