import anydbm as dbmimport cPickle as pickleclass BottleBucket(object):    '''Memory-caching wrapper around anydbm'''    def __init__(self, name):        self.__dict__['name'] = name        self.__dict__['db'] = dbm.open('%s.db' % name, 'c')        self.__dict__['mmap'] = {}    def __getitem__(self, key):        if key not in self.mmap:            self.mmap[key] = pickle.loads(self.db[key])        return self.mmap[key]    def __setitem__(self, key, value):        self.mmap[key] = value    def __delitem__(self, key):        if key in self.mmap:            del self.mmap[key]        del self.db[key]    def __getattr__(self, key):        try: return self[key]        except KeyError: raise AttributeError(key)    def __setattr__(self, key, value):        self[key] = value    def __delattr__(self, key):        try: del self[key]        except KeyError: raise AttributeError(key)    def __iter__(self):        return iter(self.ukeys())    def __contains__(self, key):        return key in self.ukeys()    def __len__(self):        return len(self.ukeys())    def keys(self):        return list(self.ukeys())    def ukeys(self):      return set(self.db.keys()) | set(self.mmap.keys())    def save(self):        self.close()        self.__init__(self.name)    def close(self):        for key in self.mmap.keys():            pvalue = pickle.dumps(self.mmap[key], pickle.HIGHEST_PROTOCOL)            if key not in self.db or pvalue != self.db[key]:                self.db[key] = pvalue        self.mmap.clear()        self.db.close()    def clear(self):        for key in self.db.keys():            del self.db[key]        self.mmap.clear()    def update(self, other):        self.mmap.update(other)    def get(self, key, default=None):        try:            return self[key]        except KeyError:            if default:                return default            raisebb = BottleBucket("testbucket") # 打开testbucket.db，读取其中内容。若testbucket.db不存在，则会创建一个。print bb.a      # 读取其中的内容print bb["b"]   # 另一种读取方式bb.c = 999      # 更新（增加）内容bb["d"]=666     # 另一种更新方式bb.save()       # 将数据pickle后保存到testbucket.db中，数据类型支持Python对象。