auto save

diy6.py

+username = "python"
+userpassword = "123456"
+i = 3
+while True:
+    if i > 0:
+        name = input("请输入你的用户名:")
+        password = input("请输入你的密码:")
+        i -= 1
+        if name == username and password == userpassword:
+            print("登录成功")
+            break
+        elif name != username:
+            print("账号错误")
+            print(""+)
+        elif password != userpassword:
+            print("密码错误")
+    else:
+        print("三次机会已用完")
+        exit()
+print("欢迎来到贝尔编程")