code: def test_backward_gpu_im2col(self):
      with testing.assert_warns(DeprecationWarning):
          self.link.to_gpu()
      with chainer.using_config("use_cudnn", "never"):
          self.check_backward(cuda.to_gpu(self.x), cuda.to_gpu(self.gy))
  
imports: import unittest
  import numpy
  import six.moves.cPickle
  import chainer
  from chainer.backends import cuda
  from chainer import gradient_check
  from chainer import links
  from chainer import testing
  from chainer.testing import attr
  from chainer.utils import conv
label_desc: Use image node_id 10 for calling the TestDilatedConvolution2D obj's underlying member method code with example usage: obj.test_backward_gpu_im2col() without return types