官方中文文档
https://dormousehole.readthedocs.io/en/latest/patterns/celery.html
官方英文文档
https://pypi.org/project/celery_once/#backends
李辉 Flask开发番外篇 https://www.zhihu.com/topic/20203769/hot
https://www.tuicool.com/articles/UziEN3I
加分布式锁 http://einverne.github.io/post/2018/01/use-celery-once-to-prevent-multiple-execution.html
https://pypi.org/project/celery_once/#backends
https://www.jianshu.com/p/b1934ff22b06
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