code: def test_forward_gpu(self):
      with testing.assert_warns(DeprecationWarning):
          self.link.to_gpu()
      self.check_forward(cuda.to_gpu(self.xs), cuda.to_gpu(self.ys))
  
imports: import itertools
  import unittest
  import numpy
  from six import moves
  import chainer
  from chainer.backends import cuda
  from chainer import initializers
  from chainer import links
  from chainer import testing
  from chainer.testing import attr
label_desc: Use image node_id 7 for calling the TestCRF1d obj's underlying member method code with example usage: obj.test_forward_gpu() without return types