code: def test_save_load_2(self):
      parent = Parent()
      parent2 = Parent2(parent.child, parent)
      # Save
      dirname = tempfile.mkdtemp()
      parent2.save(dirname)
      # Load
      parent = Parent()
      parent2 = Parent2(parent.child, parent)
      parent2.load(dirname)
  
imports: import os
  import tempfile
  import unittest
  import torch
  import pfrl
label_desc: Use image node_id 2 for calling the TestAttributeSavingMixin obj's underlying member method code with example usage: obj.test_save_load_2() without return types