给字典添加点访问

class Storage(dict):
    def __getattr__(self, key): 
        try:
            return self[key]
        except KeyError, k:
            raise AttributeError, k

    def __setattr__(self, key, value): 
        self[key] = value

    def __delattr__(self, key):
        try:
            del self[key]
        except KeyError, k:
            raise AttributeError, k

    def __repr__(self):     
        return '<Storage ' + dict.__repr__(self) + '>'