def get_game_obj(game, **kwargs):
    """
    Return a JSON-compatible read-only representation of the game state.

    Additional properties can be added using keyword arguments.

    """
    # NOTE: Set isn't JSON serializable, so we'll convert it to a list.
    return {
        'tries': game.get_tries(),
        'guesses': list(game.get_guesses()),
        'phrase': game.get_display_phrase(),
        'game_over': game.is_game_over(),
        'game_won': game.is_game_won(),
        **kwargs
    }