code: def test_call_cpu(self):
      self.check_call(
          self.model, self.imgs, self.bboxes, self.labels, self.scales
      )
  
file_path: chainercv/tests/links_tests/model_tests/light_head_rcnn_tests/test_light_head_rcnn_train_chain.py
imports: import numpy
  import unittest
  from chainer.backends import cuda
  from chainer import testing
  from chainer.testing import attr
  from chainercv.links.model.light_head_rcnn import LightHeadRCNNTrainChain
  from chainercv.utils import generate_random_bbox
  from tests.links_tests.model_tests.light_head_rcnn_tests.test_light_head_rcnn import DummyLightHeadRCNN
label_desc: Use image node_id 3 for calling the TestLightHeadRCNNTrainChain obj's underlying member method code with example usage: obj.test_call_cpu() without return types