code: def test_serialize_tensors():
      # create a temporary file and immediately release it so DGL can open it.
      f = tempfile.NamedTemporaryFile(delete=False)
      path = f.name
      f.close()
  
      tensor_dict = {
          "a": F.tensor([1, 3, -1, 0], dtype=F.int64),
          "1@1": F.tensor([1.5, 2], dtype=F.float32),
      }
  
      save_tensors(path, tensor_dict)
  
      load_tensor_dict = load_tensors(path)
  
      for key in tensor_dict:
          assert key in load_tensor_dict
          assert np.array_equal(
              F.asnumpy(load_tensor_dict[key]),
              F.asnumpy(tensor_dict[key]),
          )
  
      load_nd_dict = load_tensors(path, return_dgl_ndarray=True)
  
      for key in tensor_dict:
          assert key in load_nd_dict
          assert isinstance(load_nd_dict[key], nd.NDArray)
          assert np.array_equal(
              load_nd_dict[key].asnumpy(), F.asnumpy(tensor_dict[key])
          )
  
      os.unlink(path)
  
imports: import os
  import tempfile
  import time
  import unittest
  import warnings
  import backend
  import dgl
  import dgl.ndarray
  import numpy
  import pytest
  import scipy
  from dgl.data.utils import load_labels, load_tensors, save_tensors
label_desc: Use image node_id 6 for calling a global function with example usage: test_serialize_tensors() without return types