code: def test_backward_gpu(self):
      self.check_backward(cuda.to_gpu(self.x), cuda.to_gpu(self.gy))
  
file_path: chainer/tests/chainer_tests/functions_tests/connection_tests/test_shift.py
imports: import unittest
  import numpy
  import chainer
  from chainer import backend
  from chainer.backends import cuda
  from chainer import gradient_check
  from chainer import testing
  from chainer.testing import attr
  from chainer.testing import condition
  from chainer.functions.connection import shift
label_desc: Use image node_id 5 for calling the TestShiftFunction obj's underlying member method code with example usage: obj.test_backward_gpu() without return types