auto save

diy2.py

 username = "python"
 userpassword = "123456"
+i = 3
 while True:
+    if i>0:
         name = input("请输入用户名:")
         password = input("请输入密码:")
+        i-=1
         if name == username:
             if password == userpassword:
                 print("登录成功！")
                 print("欢迎来到贝尔编程!")
-            break
+                exit()
             print("密码错误！")
         print("用户名错误！")