最近，我每次执行时都会收到此错误sudo apt-get update。我推测我在存储库包下载尚未完全安装之前就取消了下载，从而搞砸了它。
"Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
我在网上搜索了好久，还是找不到解决方案；我试过了，--allow-unauthenticated但没得到回应command not found。我正在运行 Ubuntu 19.10