题目链接：884. 两句话中的不常见单词
找到两句哈中只出现过一次的单词即可。
from collections import Counter
from typing import List
class Solution:
def uncommonFromSentences(self, s1: str, s2: str) -> List[str]:
return [word for word, counter in Counter(f'{s1} {s2}'.split()).items() if counter == 1]