a = 'testing this is working n testing this is working 1 n'b = 'testing this is working n testing this is working 1 n testing this is working 2'splitA = set(a.split("n"))splitB = set(b.split("n"))diff = splitB.difference(splitA)diff = ", ".join(diff) # ' testing this is working 2, more things if there were...'从本质上讲，使每个字符串由一组行组成，并采用集合差-即B中所有不在A中的东西。然后取该结果并将其全部连接到一个字符串中。
编辑：这是说@ShreyasG说的一种糊涂方式-[如果x不在y中，则x用于x] …
