save project

diy2.py

@@ -6,5 +6,9 @@ while True:
     if name == username and password == userpassword:
         print("登录成功!")
         break
+    if name!=username:
+        print('用户名不存在')
+    if password!= userpassword:    
+        print('密码输入错误')
     print("用户名和密码错误!请重新输入")
 print("欢迎来到贝尔编程!")