code: def test_serialize_empty_dict():
      # 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 = {}
  
      save_tensors(path, tensor_dict)
  
      load_tensor_dict = load_tensors(path)
      assert isinstance(load_tensor_dict, dict)
      assert len(load_tensor_dict) == 0
  
      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 7 for calling a global function with example usage: test_serialize_empty_dict() without return types