def seconds_readable(seconds: int) -> str:
    """Turn seconds as an int into 'DD:HH:MM:SS'."""
    r: list[str] = []

    days, seconds = divmod(seconds, 60 * 60 * 24)
    if days:
        r.append(f"{days:02d}")

    hours, seconds = divmod(seconds, 60 * 60)
    if hours:
        r.append(f"{hours:02d}")

    minutes, seconds = divmod(seconds, 60)
    r.append(f"{minutes:02d}")

    r.append(f"{seconds % 60:02d}")
    return ":".join(r)