You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: iso.rs
    path of file: ./repos/icu4x/components/calendar/src
    
    the code of the file until where you have to start completion: // This file is part of ICU4X. For terms of use, please see the file
// called LICENSE at the top level of the ICU4X source tree
// (online at: https://github.com/unicode-org/icu4x/blob/main/LICENSE ).

//! This module contains types and implementations for the ISO calendar.
//!
//! ```rust
//! use icu::calendar::{Date, DateTime};
//!
//! // `Date` type
//! let date_is
    
    fn test_day_of_week() {
        // June 23, 2021 is a Wednesday
        assert_eq!(
            Date::try_new_iso_date(2021, 6, 23).unwrap().day_of_week(),
            IsoWeekday::Wednesday,
        );
        // Feb 2, 1983 was a Wednesday
        assert_eq!(
            Date::try_new_iso_date(1983, 2, 2).unwrap().day_of_week(),
            IsoWeekday::Wednesday,
        );
        // Jan 21, 2021 was a Tuesday
        assert_eq!(
            Date::try_new_iso_date(2020, 1, 21).unwrap().day_of_week(),
            IsoWeekday::Tuesday,
        );
    }