def force_clear_lock(self):
        '''Kick out whoever currently owns the namespace global lock.
        This is intended as purely a last-resort tool.  If another
        process has managed to get the global lock for a very long time,
        or if it requested the lock with a long expiration and then
        crashed, this can make the system functional again.  If the
        original lock holder is still alive, its session calls may fail
        with exceptions.
        '''
        return redis.Redis(connection_pool=self.pool).delete(self._lock_name)