code: def test_read_csv_line(self):
      line = b"foo1,foo2,foo3"
      expected_line = ["foo1", "foo2", "foo3"]
      self.assertEqual(
          open_images_v4_dataset_builder._read_csv_line(line),
          expected_line,
      )
  
imports: from tensorflow_datasets import testing
  from tensorflow_datasets.datasets.open_images_v4 import open_images_v4_dataset_builder
label_desc: Use image node_id 1 for calling the OpenImagesV42012Test obj's underlying member method code with example usage: obj.test_read_csv_line() without return types