sudo vim /etc/apt/sources.list
将原有内容用#注释掉，更改为：
deb http://mirrors.aliyun.com/raspbian/raspbian/ buster main contrib non-free rpi
deb-src http://mirrors.aliyun.com/raspbian/raspbian/ buster main contrib non-free rpi
修改raspbi.list 文件
sudo nano /etc/apt/sources.list.d/raspi.list
将原有内容用#注释掉，修改为：
deb http://mirrors.aliyun.com/raspbian/raspbian/ buster main
deb-src http://mirrors.aliyun.com/raspbian/raspbian/ buster main
然后更新：
sudo apt-get update
sudo apt-get upgrade