old_contents: from chainer.backends import chainerx  # NOQA
  from chainer.backends import cpu  # NOQA
  from chainer.backends import cuda  # NOQA
  from chainer.backends import intel64  # NOQA
  
new_contents: from chainer.backends import chainerx  # NOQA
  from chainer.backends import cpu  # NOQA
  from chainer.backends import cuda  # NOQA
  from chainer.backends import intel64  # NOQA
  
  
  # TODO(niboshi): Refactor registration of backend modules for functions like
  # chainer.get_device().
  
subject: Add TODO to refactor backend registration