class Scales:

    def __init__(self):
        self._assets = dict()
        self._papers = dict()

    def __getitem__(self, key):
        if isinstance(key, str):
            return self._assets.get(key)
        if isinstance(key, tuple):
            board, paper = key
            return self._papers.get((board, paper))
        return None

    def __setitem__(self, key, value: int):
        if isinstance(key, str):
            self._assets[key] = value
        elif isinstance(key, tuple):
            board, paper = key
            self._papers[(board, paper)] = value

    @property
    def has_assets(self) -> bool:
        return bool(self._assets)

    @property
    def has_papers(self) -> bool:
        return bool(self._papers)
