编辑距离，又称Levenshtein距离，是指两个字串之间，由一个转成另一个所需的最少编辑操作次数。
许可的编辑操作包括：将一个字符替换成另一个字符，插入一个字符，删除一个字符
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安装python-levenshtein：
python-Levenshtein (pip install python-levenshtein) 出现如下错误：
后来安装如下：
done
haha，终于成功了
