添加新元素后如何更新列表

因此，我正在制作此登录系统，并希望将新的用户名添加到现有列表中，然后将其保存在该列表中。

码：

def login():

usernames = ["username1", "username2", "username3"]
passwords = ["pass1", "pass2", "pass3"]

print("Login")

username = input("Username: ")
if username not in usernames:
    print("User doesn't exist")
    input("Make an account? ")
    if "yes":
        print("Account Setup")
        new_username = input("Username: ")
        usernames.append(new_username)
        print(usernames)
        new_password = input("Password: ")
        passwords.append(new_password)
        print(passwords)
        login()
    else:
        sys.exit()

else:
    password = input("Password: ")
    if password not in passwords:
        print("Incorrect password")
        login()
    elif usernames[0] != passwords[0]:
        print("Incorrect password")
        login()
    elif usernames[1] != passwords[1]:
        print("Incorrect password")
        login()
    elif usernames[2] != passwords[2]:
        print("Incorrect password")
        login()

当我添加新用户时，将保存他们的信息，但是当使用login（）并重新开始登录过程时，输入数据将丢失，我刚刚创建的帐户不再存在。

if "yes":
        print("Account Setup")
        new_username = input("Username: ")
        usernames.append(new_username)
        print(usernames)
        new_password = input("Password: ")
        passwords.append(new_password)
        print(passwords)
        login()

问题来源：stackoverflow