这段代码报KeyError错误，该如何修改：def oddString(self, words: List[str]) -> str: n = len(words) dic = {} ans = 0 for i in range(0, n): len_word = len(words[i]) diff = [ord(words[i][j]) - ord(words[i][j-1]) for j in range(1, len_word)] if tuple(diff) in dic.keys(): dic[tuple(diff)] = 0 else: dic[tuple(diff)] += 1 if dic[tuple(diff)] == 1: ans = 1 return words[ans]

这段代码会报KeyError错误，是因为在if条件语句中，当dic字典中不存在tuple(diff)这个键时，会执行dic[tuple(diff)] += 1语句，但是此时dic字典中并没有tuple(diff)这个键，所以会报KeyError错误。

为了避免这个错误，可以在if条件语句前先判断一下tuple(diff)是否已经在字典中存在，如果不存在，就先将其添加到字典中，然后再执行后面的代码。修改后的代码如下：

def oddString(self, words: List[str]) -> str:
    n = len(words)
    dic = {}
    ans = 0
    for i in range(0, n):
        len_word = len(words[i])
        diff = [ord(words[i][j]) - ord(words[i][j-1]) for j in range(1, len_word)]
        if tuple(diff) not in dic:
            dic[tuple(diff)] = 0
        if dic[tuple(diff)] == 0:
            ans = i
        dic[tuple(diff)] += 1
    return words[ans]

这里将if条件语句中的dic[tuple(diff)] == 1改为了dic[tuple(diff)] == 0，同时将ans的初始值改为0，这样就可以正确地找到奇异字符串了。