def close(self):
		'''关闭与数据库的连接'''
		if VERBOSE:
			print 'Database connection CLOSE.'
		self.conn.close()
def __getitem__(self, key):
        logger.debug("Get /%s config key", "/".join(self._path + (key,)))
        value = self._collection[key]
        return self._to_python(value)