python字符串notin

A. Python中关系运算符in，not in在字符串表达式和列表的使用时有什么区别和注意点

Membership test operations

For container types such as list, tuple, set, frozenset, dict, or collections.deque, the expressionxinyis equivalent toany(xiseorx==eforeiny).

For the string and bytes types,xinyisTrueif and only ifxis a substring ofy. An equivalent test isy.find(x)!=-1. Empty strings are always considered to be a substring of any other string, so""in"abc"will returnTrue.

翻译：

对容器类型，例如list、tuple、set、frozenset、dict或collections.deque，表达式x in y等价于any(x is e or x == e for e in y)。

对字符串和bytes类型，x in y为真当且仅当x是y的子串。等价测试为y.find(x) != -1。空字符串永远被视作是其他任何字符串的子集，因此"" in "abc"将返回True。