parameterising tests (python) missing decorator in code

[TomMonks]

When giving the example of using the decorator to run multiple tests in one go the decorator is omitted form the example code

def test_summary_stats(
    data, expected_mean, expected_std, expected_ci_lower, expected_ci_upper
):
    """Running summary_stats returns expected values."""
    res = summary_stats(pd.Series(data))
    assert res["mean"] == pytest.approx(expected_mean, rel=5e-3)
    assert res["std_dev"] == pytest.approx(expected_std, rel=5e-3)
    assert res["ci_lower"] == pytest.approx(expected_ci_lower, rel=5e-3)
    assert res["ci_upper"] == pytest.approx(expected_ci_upper, rel=5e-3)

should be

@pytest.mark.parametrize(
    "data, expected_mean, expected_std, expected_ci_lower, expected_ci_upper",
    [
        # Five value sample with known summary statistics
        ([1.0, 2.0, 3.0, 4.0, 5.0], 3.0, 1.58, 1.04, 4.96),
        # No variation: CI collapse to mean
        ([5, 5, 5], 5, 0, 5, 5),
    ],
)
def test_summary_stats(
    data, expected_mean, expected_std, expected_ci_lower, expected_ci_upper
):
    """Running summary_stats returns expected values."""
    res = summary_stats(pd.Series(data))
    assert res["mean"] == pytest.approx(expected_mean, rel=5e-3)
    assert res["std_dev"] == pytest.approx(expected_std, rel=5e-3)
    assert res["ci_lower"] == pytest.approx(expected_ci_lower, rel=5e-3)
    assert res["ci_upper"] == pytest.approx(expected_ci_upper, rel=5e-3)