deb http://mirrors.aliyun.com/debian/ bullseye main contrib non-free
deb http://mirrors.aliyun.com/debian/ bullseye-updates main contrib non-free
deb http://mirrors.aliyun.com/debian/ bullseye-backports main contrib non-free
deb http://mirrors.aliyun.com/debian-security bullseye-security main contrib non-free