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https://qastack.cn/programming/22892120/how-to-generate-a-random-string-of-a-fixed-length-in-go

生产随机数：https://blog.csdn.net/u011304970/article/details/72721747

高性能 go 生成指定长度随机字符串：https://blog.csdn.net/lsmsrc/article/details/104652533