code: def test_download_only():
      with mock.patch(
          "tensorflow_datasets.download.DownloadManager.download"
      ) as mock_download:
          assert not _build("dummy_dataset_no_generate --download_only")
          mock_download.assert_called_with(
              {"file0": "http://data.org/file1.zip"}
          )
  
imports: import contextlib
  import os
  import pathlib
  from typing import Dict, Iterator, List, Optional
  from unittest import mock
  from absl.testing import parameterized
  from etils import epath
  import pytest
  import tensorflow_datasets
  from tensorflow_datasets import testing
  from tensorflow_datasets.core import download
  from tensorflow_datasets.core import utils
  from tensorflow_datasets.core.utils import file_utils
  from tensorflow_datasets.scripts.cli import build
  from tensorflow_datasets.scripts.cli import main
label_desc: Use image node_id 15 for calling a global function with example usage: test_download_only() without return types