class_docstr: Copies the input variable onto the specified device.
code: def backward(self, indexes, grad_outputs):
      f = Copy(self.out_device, self._in_device)
      return f.apply(grad_outputs)
  
file_path: chainer/chainer/functions/array/copy.py
imports: import chainer
  from chainer import backend
  from chainer.backends import cuda
  from chainer import function_node
  from chainer.utils import type_check
  import chainerx
label_desc: Use image node_id 5 for calling the Copy obj's underlying member method code with example usage: obj.backward(indexes, grad_outputs) and returns: f