うぐげぇ、疲れられた。
これな:
In this example, the barrier enforces a rule that votes cannot be counted at any polling site until all polls are closed. Notice how a solution with a barrier is similar to one with :meth:`threading.Thread.join`, but the threads stay alive and continue to do work (summarizing ballots) after the barrier point is crossed.
…
In this example, the barrier enforces a more robust rule. If some election sites do not finish before midnight, the barrier times-out and the ballots are sealed and deposited in a queue for later handling.
なお、知恵袋は…、役に立ったような立たなかったような…。袋なくてもあってもあんまり変わらなかった気もする。