auto save

diy2.py

 username = "python"
 userpassword = "123456"
 while True:
-    name = input("请输入用户名:")
-    password = input("请输入密码:")
-    if name == username and password == userpassword:
-        print("登录成功!")
-        break
-    if name != username:
+    name = input("请输入用户名:")#输入用户名
+    password = input("请输入密码:")#输入密码
+    if name == username and password == userpassword:#如果对
+        print("登录成功!")#就登录成功
+        break#跳
+    if name != username:#如果用户名错误
         print("用户名错误")
     if name != userpassword:
         print("密码错误