utils.py 文件源码

def memoized(func):
    _cache = {}

    def _deco(*args, **kwargs):
        if 'clear_cache' in kwargs or 'clear_cache_only' in kwargs:
            _cache.clear()
            if 'clear_cache_only' in kwargs:
                return  # we don't care about the output
            del kwargs['clear_cache']
        if not isinstance(args, collections.Hashable):
            return func(*args, **kwargs)
        if args in _cache:
            return _cache[args]
        else:
            value = func(*args, **kwargs)
            _cache[args] = value
            return value

    return update_wrapper(_deco, func)