def get_message(
    items: list[str], sort: bool = False, oxford: bool = True, separator: str = ","
) -> str:
    """Get message.

    >>> get_message(["chips", "pie", "soda"], separator=";")
    'You are bringing chips; pie; and soda.'
    >>> get_message(["chips", "pie", "soda"], oxford=False)
    'You are bringing chips, pie and soda.'
    >>> get_message([])
    Traceback (most recent call last):
    ValueError: Empty list.
    """
    if not items:
        raise ValueError("Empty list.")
    items.sort() if sort else items
    connect = f"{separator if oxford and len(items) > 2 else ''} and " if len(items) > 1 else ""
    return f"You are bringing {f'{separator} '.join(items[:-1])}{connect}{items[-1]}."