auto save

diy2.py

+i=3
+username = "python"
+userpassword = "123456"
+while True:
+    if i>0:
+        name = input("请输入用户名:")
+        password = input("请输入密码:")
+        i=i-1
+        if name == username and password == userpassword:
+            print("登录成功!")
+            break
+        if name != username:
+            print("用户名有误")
+            print("你还有"+str(i)+"次机会")
+            continue
+        if password != userpassword:
+            print("密码有误")
+            print("你还有"+str(i)+"次机会")
+    else:
+        print("请拿身份到我们银行解冻")
+        exit()
+print("欢迎进入我们系统")