请问下，ubuntu18.04安装purseaudio失败怎么解决呢，报错信息如下：
E: The repository 'http://ppa.launchpad.net/therealkenc/wsl-pulseaudio/ubuntu focal Release' does not have a Release file. N: 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
请问下，ubuntu18.04安装purseaudio失败怎么解决呢，报错信息如下： E: The repository 'http://ppa.launchpad.net/therealkenc/wsl-pulseaudio/ubuntu focal Release' does not have a Release file. N: 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