Function convert

src/datetime.rs:324–330

(py: Python<'py>, expected_value: i64)

    fn unit_conversion() {
        #[track_caller]
        fn convert<'py, S: Unit, D: Unit>(py: Python<'py>, expected_value: i64) {
            let array = PyArray1::<Timedelta<S>>::from_slice(py, &[Timedelta::<S>::from(1)]);
            let array = array.cast_array::<Timedelta<D>>(false).unwrap();

            let value: i64 = array.get_owned(0).unwrap().into();
            assert_eq!(value, expected_value);
        }

        Python::attach(|py| {
            convert::<units::Years, units::Days>(py, (97 + 400 * 365) / 400);