code: def _check_decode(self, mb_loc, mb_conf):
      xp = self.coder.xp
  
      bbox, label, score = self.coder.decode(
          mb_loc, mb_conf, self.nms_thresh, self.score_thresh
      )
  
      self.assertIsInstance(bbox, xp.ndarray)
      self.assertEqual(bbox.ndim, 2)
      self.assertLessEqual(bbox.shape[0], self.n_bbox * self.n_fg_class)
      self.assertEqual(bbox.shape[1], 4)
  
      self.assertIsInstance(label, xp.ndarray)
      self.assertEqual(label.ndim, 1)
      self.assertEqual(label.shape[0], bbox.shape[0])
  
      self.assertIsInstance(score, xp.ndarray)
      self.assertEqual(score.ndim, 1)
      self.assertEqual(score.shape[0], bbox.shape[0])
  
file_path: chainercv/tests/links_tests/model_tests/ssd_tests/test_multibox_coder.py
imports: import numpy
  import unittest
  from chainer.backends import cuda
  from chainer import testing
  from chainer.testing import attr
  from chainercv.links.model.ssd import MultiboxCoder
label_desc: Use image node_id 8 for calling the TestMultiboxCoder obj's underlying member method code with example usage: obj._check_decode(mb_loc, mb_conf) without return types