time.sleep(2 ** attempt) # 指数退避
用产品经理的心态对待咖啡，不断迭代好喝的咖啡。公众号：咖啡平方，更多细节参见谷歌浏览器【最新下载地址】
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"And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day."，详情可参考Line官方版本下载