code: def test_dc_test_base():
      class TestDummyCollection(dc_testing.DatasetCollectionTestBase):
          DATASET_COLLECTION_CLASS = testing.DummyDatasetCollection
  
      # Check defaults class attributes are set up correctly.
      assert TestDummyCollection.VERSION is None
      assert not TestDummyCollection.DATASETS_TO_TEST
      assert TestDummyCollection.CHECK_DATASETS_VERSION
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_dc_test_base() without return types