python - 列表中的字典

Question

假设我有这个列表:

a=[ {"user":"John","password":"123"} , {"user":"Mike","password":"12345"} ,{"user":"Peter","password":"qwerty"}]

user=input("insert your username")
password=input("insert your password")

现在我想知道输入的用户名和密码是否在前面的列表中，我该如何解决这个问题？

如果我现在想要有 3 种情况:一种是用户和密码匹配，第二种是用户名正确但密码不正确，最后一种是用户名不存在。

if {'user':user,'password':password} in a:
    print("okay")
else:
    if {'user':user} in a and {'password':password} not in a:
        print("user okay, but incorrect pass")
    else:
        print("No username")

这种类型的代码行不通，对吧？那么我该如何解决第二步(在第一步之后)？

Answer 1

使用:

if {'user':user,'password':password} in a:
    # it is already in there
else:
    # it isn't in there

编辑

使用:

if {'user':user,'password':password} in a:
    # it is already in there
elif any(user == i['user'] and password != i['password'] for i in a):
    # user name is correct, but password isn't
else:
    # it isn't in there