code: def _updated_array(self, backend_config, loss_scale):
      arr = np.arange(3, dtype=np.float32)
      param = chainer.Parameter(arr)
      link = chainer.Link()
      with link.init_scope():
          link.p = param
      link.to_device(backend_config.device)
      opt = optimizers.SGD(lr=1)
      opt.setup(link)
      opt.add_hook(optimizer_hooks.WeightDecay(1 / 8.0))
      loss = F.sum(link.p**3)
      loss.backward(loss_scale=loss_scale)
      opt.update()
      return link.p.array
  
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 2 for calling the TestWeightDecayLossScale obj's underlying member method code with example usage: obj._updated_array(backend_config, loss_scale) and returns: link