code: def test_weight_decay_loss_scale(self, backend_config):
      a = self._updated_array(backend_config, None)
      b = self._updated_array(backend_config, loss_scale=4.0)
      testing.assert_allclose(a, b)
  
file_path: chainer/tests/chainer_tests/optimizer_hooks_tests/test_weight_decay.py
imports: import unittest
  import numpy
  import chainer
  import chainer.functions
  from chainer import optimizer_hooks
  from chainer import optimizers
  from chainer import testing
  import utils
label_desc: Use image node_id 1 for calling the TestWeightDecayLossScale obj's underlying member method code with example usage: obj.test_weight_decay_loss_scale(backend_config) without return types