登陸和注冊功能
代碼如下

import json
user = []
with open('user.json', 'r') as fp:
    user = json.load(fp)


def region():
    while 1:
        user1 = input('請輸入用戶名：')
        password1 = input('請輸入密碼：')
        us = False
        true = False
        if user == []:
            print('此系統(tǒng)還沒有人注冊，請注冊')
            print('是否注冊：1.是 2.否')
            n = int(input('請選擇：'))
            if n == 1:
                register()
            else:
                break
        for user2 in user:
            if user2['user'] == user1:
                us = True
                if user2['user'] == user1 and user2['password'] == password1:
                    true = True
        if us == False:
            print('用戶名不存在！')
            break
        elif true:
            print('登陸成功！')
            break
        else:
            print('用戶名或密碼錯誤，請重新輸入，是否重新輸入：1.是 2.否')
            n = int(input('請選擇：'))
            if n == 1:
                continue
            else:
                break


def register():
    while 1:
        user3 = input('請輸入用戶名：')
        password1 = input('請輸入密碼：')
        password2 = input('請確認密碼：')
        name = False
        if password1 != password2:
            print('兩次密碼不一致，請重新輸入！')
            continue
        for user2 in user:
            if user2['user'] == user3:
               name = True
        if name:
            print('用戶名已存在,請重新輸入!')
            continue
        user_ = {'user': user3, 'password': password1}
        user.append(user_)
        break
    with open('user.json', 'w') as fp:
        json.dump(user, fp)
    print('注冊成功！')

while 1:
    print('==============================')
    print('|    歡迎來到學生管理系統(tǒng)    |')
    print('==============================')
    print('|        1.用戶登陸          |')
    print('|        2.用戶注冊          |')
    print('==============================')
    n = int(input('請選擇：'))
    if n == 1:
        region()
    elif n == 2:
        register()
    else:
        print('您已退出系統(tǒng)！')
        break