code: def test_loc2bbox_cpu(self):
      self.check_loc2bbox(self.src_bbox, self.loc, self.dst_bbox)
  
imports: import unittest
  import numpy
  from chainer.backends import cuda
  from chainer import testing
  from chainer.testing import attr
  from chainercv.links.model.faster_rcnn import bbox2loc
  from chainercv.links.model.faster_rcnn import loc2bbox
  from chainercv.utils import generate_random_bbox
label_desc: Use image node_id 6 for calling the TestLocBboxConversions obj's underlying member method code with example usage: obj.test_loc2bbox_cpu() without return types