seo优化_前端开发_渗透技术在python中，要判断特定的值是否存在列表中，可使用关键字in,判断特定的值不存在列表中，可使用关键字not in
letters = ['A','B','C','D','E','F','G']
if 'A' in letters:
print('A'+' exists')
if 'h' not in letters:
print('h'+' not exists')
打印结果：
A exists
h not exists
一个稍微复杂的案例
定义2个列表分别为list_01跟list_02
list_01 = ['A','B','C','H'] list_02 = ['A','B','E','F']
通过判断查看list_01在list_02中的存在情况
list_01 = ['A','B','C','H']
list_02 = ['A','B','E','F']
for letter in list_01:
if letter in list_02:
print(letter+' is exists')
else:
print(letter+' is not exists')
打印结果：
A is exists
B is exists
C is not exists
H is not exists
