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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 clear(self, namespace=None, _conn=None):
 """ Clears the cache in the cache namespace. If an alternative namespace is given, it will clear those ones instead. :param namespace: str alternative namespace to use :param timeout: int or float in seconds specifying maximum timeout for the operations to last :returns: True :raises: :class:`asyncio.TimeoutError` if it lasts more than self.timeout """

        start = time.monotonic()
        ret = await self._clear(namespace, _conn=_conn)
        logger.debug("CLEAR %s %d (%.4f)s", namespace, ret, time.monotonic() - start)
        return ret