Ubuntu 20.04 LTS (Focal Fossa) sed -i '1,$d' /etc/apt/sources.list && tee -a /etc/apt/sources.list > /dev/null <<EOL
deb http://mirrors.ustc.edu.cn/ubuntu/ focal main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ focal-security main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ focal-updates main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ focal-proposed main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ focal-backports main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ focal main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ focal-security main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ focal-updates main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ focal-proposed main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ focal-backports main restricted universe multiverse
EOL
apt-get update --allow-releaseinfo-change
Ubuntu 22.04 LTS (Jammy Jellyfish) sed -i '1,$d' /etc/apt/sources.list && tee -a /etc/apt/sources.list > /dev/null <<EOL
deb http://mirrors.ustc.edu.cn/ubuntu/ jammy main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ jammy-security main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ jammy-updates main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ jammy-proposed main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ jammy-backports main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ jammy main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ jammy-security main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ jammy-updates main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ jammy-proposed main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ jammy-backports main restricted universe multiverse
EOL
apt-get update --allow-releaseinfo-change
Ubuntu 23.04 (Lunar Lobster) sed -i '1,$d' /etc/apt/sources.list && tee -a /etc/apt/sources.list > /dev/null <<EOL
deb http://mirrors.ustc.edu.cn/ubuntu/ lunar main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ lunar-security main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ lunar-updates main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ lunar-proposed main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ lunar-backports main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ lunar main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ lunar-security main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ lunar-updates main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ lunar-proposed main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ lunar-backports main restricted universe multiverse
EOL
apt-get update --allow-releaseinfo-change
sed -i '1,$d' /etc/apt/sources.list && tee -a /etc/apt/sources.list > /dev/null <<EOL
deb https://mirrors.ustc.edu.cn/ubuntu/ noble main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ noble main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ noble-security main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ noble-security main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ noble-updates main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ noble-updates main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ noble-backports main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ noble-backports main restricted universe multiverse
EOL
apt-get update --allow-releaseinfo-change
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