code: def test_save_load(data_pack):
      dirpath = ".tmpdir"
      data_pack.save(dirpath)
      dp = load_data_pack(dirpath)
      with pytest.raises(FileExistsError):
          data_pack.save(dirpath)
      assert len(data_pack) == 2
      assert len(dp) == 2
      shutil.rmtree(dirpath)
  
imports: import shutil
  import pandas
  import pytest
  from matchzoo import DataPack, load_data_pack
label_desc: Use image node_id 4 for calling a global function with example usage: test_save_load(data_pack) without return types