code: def test_shared_link_copy(self):
      head = L.Linear(2, 2)
      model_a = chainer.ChainList(head.copy(), L.Linear(2, 3))
      model_b = chainer.ChainList(head.copy(), L.Linear(2, 4))
      a_params = dict(model_a.namedparams())
      b_params = dict(model_b.namedparams())
      self.assertEqual(
          a_params["/0/W"].array.ctypes.data,
          b_params["/0/W"].array.ctypes.data,
      )
      self.assertEqual(
          a_params["/0/b"].array.ctypes.data,
          b_params["/0/b"].array.ctypes.data,
      )
      import copy
  
      model_a_copy = copy.deepcopy(model_a)
      model_b_copy = copy.deepcopy(model_b)
      a_copy_params = dict(model_a_copy.namedparams())
      b_copy_params = dict(model_b_copy.namedparams())
      # When A and B are separately deepcopied, head is no longer shared
      self.assertNotEqual(
          a_copy_params["/0/W"].array.ctypes.data,
          b_copy_params["/0/W"].array.ctypes.data,
      )
      self.assertNotEqual(
          a_copy_params["/0/b"].array.ctypes.data,
          b_copy_params["/0/b"].array.ctypes.data,
      )
  
      model_total_copy = copy.deepcopy(
          chainer.ChainList(model_a, model_b)
      )
      model_a_copy = model_total_copy[0]
      model_b_copy = model_total_copy[1]
      a_copy_params = dict(model_a_copy.namedparams())
      b_copy_params = dict(model_b_copy.namedparams())
      # When ChainList(A, B) is deepcopied, head is still shared!
      self.assertEqual(
          a_copy_params["/0/W"].array.ctypes.data,
          b_copy_params["/0/W"].array.ctypes.data,
      )
      self.assertEqual(
          a_copy_params["/0/b"].array.ctypes.data,
          b_copy_params["/0/b"].array.ctypes.data,
      )
  
imports: import multiprocessing
  import os
  import signal
  import sys
  import unittest
  import warnings
  import chainer
  import chainer.links
  from chainer import optimizers
  import copy
  import numpy
  import chainerrl
  from chainerrl.misc import async_
label_desc: Use image node_id 7 for calling the TestAsync obj's underlying member method code with example usage: obj.test_shared_link_copy() without return types