apt-get update出现错误 ‘E: Problem executing scripts APT::Update::Post-Invoke-Success 'if /usr/bin/test’

在终端执行以下代码：

sudo pkill -KILL appstreamcli`
wget -P /tmp https://launchpad.net/ubuntu/+archive/primary/+files/appstream_0.9.4-1ubuntu1_amd64.deb https://launchpad.net/ubuntu/+archive/primary/+files/libappstream3_0.9.4-1ubuntu1_amd64.debdpkg -i /tmp/appstream_0.9.4-1ubuntu1_amd64.deb
``