code: def check_serialization(self, backend_config):
      with utils.tempdir() as root:
          filename = os.path.join(root, "tmp.npz")
  
          layer1 = self.layer.copy("copy")
          hook1 = copy.deepcopy(self.hook)
          layer1.add_hook(hook1)
  
          layer1.to_device(backend_config.device)
          x = backend_config.get_array(self.x)
          with backend_config:
              layer1(x)
              with chainer.using_config("train", False):
                  y1 = layer1(x)
          serializers.save_npz(filename, layer1)
  
          layer2 = self.layer.copy("copy")
          hook2 = copy.deepcopy(self.hook)
          layer2.add_hook(hook2)
  
          # Test loading is nice.
          msg = None
          try:
              serializers.load_npz(filename, layer2)
          except Exception as e:
              msg = e
          assert msg is None
  
          with chainer.using_config("train", False):
              y2 = layer2(self.x.copy())
  
          # Test attributes are the same.
          orig_weight = _cpu._to_cpu(
              getattr(layer1, hook1.weight_name).array
          )
          orig_vector = _cpu._to_cpu(getattr(layer1, hook1.vector_name))
          numpy.testing.assert_array_equal(
              orig_weight, getattr(layer2, hook2.weight_name).array
          )
          numpy.testing.assert_array_equal(
              orig_vector, getattr(layer2, hook2.vector_name)
          )
          testing.assert_allclose(y1.array, y2.array)
  
imports: import copy
  import os
  import unittest
  import numpy
  import pytest
  import chainer
  from chainer.backends import _cpu
  from chainer.link_hooks.spectral_normalization import SpectralNormalization
  import chainer.links
  from chainer import serializers
  from chainer import testing
  from chainer.testing import attr
  from chainer.testing.backend import BackendConfig
  from chainer import utils
label_desc: Use image node_id 16 for calling the BaseTest obj's underlying member method code with example usage: obj.check_serialization(backend_config) without return types