翻译代码？
Router(config)#access-list 1 permit host 172.16.1.12① ________
Router(config)#access-list 1 deny any ② ________
Router(config)#interface serial 2/0③________
Router(config-if)# no shutdown④ ________
Router(config-if)# ip access-group 1 in ⑤________
