code: def test_forward_cpu(self):
      self.check_forward(self.log_pi, self.tau)
  
file_path: chainer/tests/chainer_tests/functions_tests/noise_tests/test_gumbel_softmax.py
imports: import unittest
  import numpy
  import chainer
  from chainer import backend
  from chainer.backends import cuda
  from chainer import functions
  from chainer import testing
  from chainer.testing import attr
label_desc: Use image node_id 3 for calling the TestGumbelSoftmax obj's underlying member method code with example usage: obj.test_forward_cpu() without return types