deb http://mirrors.163.com/debian/ buster main non-free contrib deb http://mirrors.163.com/debian/ buster-updates main non-free contrib deb http://mirrors.163.com/debian/ buster-backports main non-free contrib deb-src http://mirrors.163.com/debian/ buster main non-free contrib deb-src http://mirrors.163.com/debian/ buster-updates main non-free contrib deb-src http://mirrors.163.com/debian/ buster-backports main non-free contrib deb http://mirrors.163.com/debian-security/ buster/updates main non-free contrib deb-src http://mirrors.163.com/debian-security/ buster/updates main non-free contrib