code: def test_forward_gpu(self):
      with testing.assert_warns(DeprecationWarning):
          self.link.to_gpu()
      self.check_forward(cuda.to_gpu(self.x))
  
file_path: chainer/tests/chainer_tests/links_tests/connection_tests/test_highway.py
imports: import unittest
  import numpy
  import chainer
  from chainer.backends import cuda
  from chainer import functions
  from chainer import gradient_check
  from chainer import links
  from chainer import testing
  from chainer.testing import attr
label_desc: Use image node_id 5 for calling the TestHighway obj's underlying member method code with example usage: obj.test_forward_gpu() without return types