code: def __exit__(self, typ, value, traceback):
      for c in reversed(self.contexts):
          c.__exit__(typ, value, traceback)
  
imports: from __future__ import absolute_import
  import warnings
  import weakref
  import six
  import chainer
  from chainer import backend
  from chainer.backends import cuda
  from chainer import configuration
  from chainer.function_hook import FunctionHook
  from chainer import function_node
  from chainer import variable
  import chainerx
label_desc: Use image node_id 3 for calling the _BackpropModeContext obj's underlying member method code with example usage: obj.__exit__(typ, value, traceback) without return types