树莓派配置apt源

1.sudo nano /etc/apt/sources.list
deb http://mirrors.tuna.tsinghua.edu.cn/debian/ buster main contrib non-free
deb http://mirrors.tuna.tsinghua.edu.cn/debian/ buster-updates main contrib non-free
deb http://mirrors.tuna.tsinghua.edu.cn/debian/ buster-backports main contrib non-free
deb http://mirrors.tuna.tsinghua.edu.cn/debian-security buster/updates main contrib non-free