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                        - Types: deb
 - URIs: https://mirrors.tuna.tsinghua.edu.cn/ubuntu
 - Suites: noble noble-updates noble-backports
 - Components: main restricted universe multiverse
 - Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
 - 
 - # 默认注释了源码镜像以提高 apt update 速度,如有需要可自行取消注释
 - # Types: deb-src
 - # URIs: https://mirrors.tuna.tsinghua.edu.cn/ubuntu
 - # Suites: noble noble-updates noble-backports
 - # Components: main restricted universe multiverse
 - # Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
 - 
 - # 以下安全更新软件源包含了官方源与镜像站配置,如有需要可自行修改注释切换
 - Types: deb
 - URIs: https://mirrors.tuna.tsinghua.edu.cn/ubuntu
 - Suites: noble-security
 - Components: main restricted universe multiverse
 - Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
 - 
 - # Types: deb-src
 - # URIs: https://mirrors.tuna.tsinghua.edu.cn/ubuntu
 - # Suites: noble-security
 - # Components: main restricted universe multiverse
 - # Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
 - 
 - # 预发布软件源,不建议启用
 - 
 - # Types: deb
 - # URIs: https://mirrors.tuna.tsinghua.edu.cn/ubuntu
 - # Suites: noble-proposed
 - # Components: main restricted universe multiverse
 - # Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
 - 
 - # # Types: deb-src
 - # # URIs: https://mirrors.tuna.tsinghua.edu.cn/ubuntu
 - # # Suites: noble-proposed
 - # # Components: main restricted universe multiverse
 - # # Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
 
 
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