我正在尝试安装 NVIDIA Container Toolkit。设置存储库并指定 GPG 密钥的命令是：
distribution=$(. /etc/os-release;echo $ID$VERSION_ID) \
&& curl -fsSL https://nvidia.github.io/libnvidia-container/gpgkey | sudo gpg --dearmor -o /usr/share/keyrings/nvidia-container-toolkit-keyring.gpg \
&& curl -s -L https://nvidia.github.io/libnvidia-container/$distribution/libnvidia-container.list | \
sed 's#deb https://#deb [signed-by=/usr/share/keyrings/nvidia-container-toolkit-keyring.gpg] https://#g' | \
sudo tee /etc/apt/sources.list.d/nvidia-container-toolkit.list
但是，我没有文件/etc/os-release。我期望它/etc/os-release旨在提供有关我的操作系统（即 Ubuntu 20.04）的信息。我确实有两个文件，它们似乎具有相似的意图，但不可执行：/usr/lib/os-release和/etc/debian文件。
其内容/usr/lib/os-release 为：
$ cat /usr/lib/os-release
NAME="Ubuntu"
VERSION="20.04.4 LTS (Focal Fossa)"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 20.04.4 LTS"
VERSION_ID="20.04"
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
VERSION_CODENAME=focal
UBUNTU_CODENAME=focal
其内容/etc/debian_version为：
$ cat /etc/debian_version
bullseye/sid
最后，如果我执行lsb_release -a，我会得到：
$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 20.04.4 LTS
Release: 20.04
Codename: focal
那么我需要用什么来代替
distribution=$(. /etc/os-release;echo $ID$VERSION_ID)