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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:

def manage_actor(self, monitor, actor, stop=False):
        '''If an actor failed to notify itself to the arbiter for more than
        the timeout, stop the actor.

        :param actor: the :class:`Actor` to manage.
        :param stop: if ``True``, stop the actor.
        :return: if the actor is alive 0 if it is not.
        '''
        if not monitor.is_running():
            stop = True
        if not actor.is_alive():
            if not actor.should_be_alive() and not stop:
                return 1
            actor.join()
            self._remove_monitored_actor(monitor, actor)
            return 0
        timeout = None
        started_stopping = bool(actor.stopping_start)
        # if started_stopping is True, set stop to True
        stop = stop or started_stopping
        if not stop and actor.notified:
            gap = time() - actor.notified
            stop = timeout = gap > actor.cfg.timeout
        if stop:   # we are stopping the actor
            dt = actor.should_terminate()
            if not actor.mailbox or dt:
                if not actor.mailbox:
                    monitor.logger.warning('kill %s - no mailbox.', actor)
                else:
                    monitor.logger.warning('kill %s - could not stop '
                                           'after %.2f seconds.', actor, dt)
                actor.kill()
                self._remove_monitored_actor(monitor, actor)
                return 0
            elif not started_stopping:
                if timeout:
                    monitor.logger.warning('Stopping %s. Timeout %.2f',
                                           actor, timeout)
                else:
                    monitor.logger.info('Stopping %s.', actor)
                actor.stop()
        return 1