泰山派更换软件源
1、编辑apt软件包源获取文件
vim /etc/apt/sources.list
2、更换为下面的源
deb http://mirrors.ustc.edu.cn/ubuntu-ports/ focal main multiverse restricted universe
deb http://mirrors.ustc.edu.cn/ubuntu-ports/ focal-backports main multiverse restricted universe
deb http://mirrors.ustc.edu.cn/ubuntu-ports/ focal-proposed main multiverse restricted universe
deb http://mirrors.ustc.edu.cn/ubuntu-ports/ focal-security main multiverse restricted universe
deb http://mirrors.ustc.edu.cn/ubuntu-ports/ focal-updates main multiverse restricted universe
deb-src http://mirrors.ustc.edu.cn/ubuntu-ports/ focal main multiverse restricted universe
deb-src http://mirrors.ustc.edu.cn/ubuntu-ports/ focal-backports main multiverse restricted universe
deb-src http://mirrors.ustc.edu.cn/ubuntu-ports/ focal-proposed main multiverse restricted universe
deb-src http://mirrors.ustc.edu.cn/ubuntu-ports/ focal-security main multiverse restricted universe
deb-src http://mirrors.ustc.edu.cn/ubuntu-ports/ focal-updates main multiverse restricted universe
3、更新源
sudo apt update
4、测试下载
apt-get install git