save project

diy2.py

+O=3
 username = "python" 
 userpassword = "123456"
 while True: 
+    if O>0:
         a = input("请输入用户名:")
         d = input("请输入密码:")  
-    if name == username and password == userpassword:  
+        o-=1
+        if a == username and d == userpassword:  
             break
             print("登录成功!")  
         if a!=username:
             print("有户名错误")  
         if d!=userpassword:
-        print("密码错误"")
+            print("密码错误")   
+    else:
+        print("无法登录")  
+        exit()
     print("用户名和密码错误!请重新输入")  
 print("欢迎来到贝尔编程!")
\ No newline at end of file