code: def test_gpu(self):
      self._test(chainer.cuda.cupy)
  
file_path: chainerrl/tests/misc_tests/test_conjugate_gradient.py
imports: import unittest
  import chainer
  from chainer import testing
  from chainer.testing import condition
  import numpy
  import chainerrl
label_desc: Use image node_id 3 for calling the TestConjugateGradient obj's underlying member method code with example usage: obj.test_gpu() without return types