https://blog.wongcw.com/2020/01/26/%e8%b0%b7%e6%ad%8c%e6%89%93%e9%80%a0%e5%ae%89%e5%8d%93%e7%89%88airdrop%ef%bc%9a%e6%96%b0%e5%8a%9f%e8%83%bd%e5%b0%87%e9%9b%86%e6%88%90%e5%88%b0%e6%96%b0%e7%89%88%e4%b8%ad/