class _AllStatsSentinel:
    """Sentinel для обозначения 'любые навыки'"""
    _instance = None

    def __new__(cls):
        if cls._instance is None:
            cls._instance = super().__new__(cls)
        return cls._instance

    def __repr__(self):
        return "ALL_STATS"

    def __eq__(self, other: object) -> bool:
        return isinstance(other, _AllStatsSentinel)

    def __hash__(self) -> int:
        return hash("ALL_STATS")