For openSUSE Leap 15.5 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:wicked:qubes-build/openSUSE_Leap_15.5/home:wicked:qubes-build.repo
zypper refresh
zypper install python-html5lib
For openSUSE Leap 15.4 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:wicked:qubes-build/openSUSE_Leap_15.4/home:wicked:qubes-build.repo
zypper refresh
zypper install python-html5lib
For openSUSE Leap 15.3 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:wicked:qubes-build/openSUSE_Leap_15.3/home:wicked:qubes-build.repo
zypper refresh
zypper install python-html5lib
For SLE 15 SP4 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:wicked:qubes-build/SLE_15_SP4/home:wicked:qubes-build.repo
zypper refresh
zypper install python-html5lib