code: def test_transform() -> None:
      indices = list(range(12))
      transform = utils.Transform(indices, rotation=True)
      assert transform.rotation_matrix is not None
      rot: np.ndarray = transform.rotation_matrix
      np.testing.assert_array_almost_equal(
          rot.T.dot(rot), np.identity(12)
      )
      x = np.random.normal(0, 1, 16)
      y = transform(x)
      np.testing.assert_equal(len(y), 12)
      np.testing.assert_array_equal(y, transform(x))
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_transform() without return types