code: def test_save_load_buf2(self):
      # Initialize the model
      model = linearModel()
      buf = io.BytesIO()
      torch.save(model.state_dict(), buf, encryption_key=encryption_key)
      model.linear.weight.data.fill_(1.110)
      # now we try to load it back, and check the weight is the same
      model.load_state_dict(
          torch.load(buf, decryption_key=encryption_key)
      )
      self.assertEqual(model.linear.weight.data[0], 1.245)
  
imports: import torch.nn.functional
  import torch, os, io
  import base64
  import torch.nn
  import unittest
  import random
  from bigdl.nano.pytorch.patching import patch_encryption
  import torch.optim
label_desc: Use image node_id 4 for calling the TestModelSaveLoad obj's underlying member method code with example usage: obj.test_save_load_buf2() without return types