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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 async def expire(self, key, ttl, namespace=None, _conn=None):
 """ Set the ttl to the given key. By setting it to 0, it will disable it :param key: str key to expire :param ttl: int number of seconds for expiration. If 0, ttl is disabled :param namespace: str alternative namespace to use :param timeout: int or float in seconds specifying maximum timeout for the operations to last :returns: True if set, False if key is not found :raises: :class:`asyncio.TimeoutError` if it lasts more than self.timeout """

        start = time.monotonic()
        ns_key = self.build_key(key, namespace=namespace)
        ret = await self._expire(ns_key, ttl, _conn=_conn)
        logger.debug("EXPIRE %s %d (%.4f)s", ns_key, ret, time.monotonic() - start)
        return ret