code: def test_call_cpu(self):
      self.check_call()
  
file_path: chainercv/tests/links_tests/model_tests/vgg_tests/test_vgg16.py
imports: import unittest
  import numpy
  import chainer
  from chainer.initializers import Zero
  from chainer.testing import attr
  from chainer import Variable
  from chainercv.links import VGG16
  from chainercv.utils import testing
label_desc: Use image node_id 3 for calling the TestVGG16Call obj's underlying member method code with example usage: obj.test_call_cpu() without return types