Para openSUSE Leap 15.2 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/server:Kolab:16.0/openSUSE_Leap_15.2/server:Kolab:16.0.repo
zypper refresh
zypper install python-icalendar
Para openSUSE Leap 15.1 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/server:Kolab:16.0/openSUSE_Leap_15.1/server:Kolab:16.0.repo
zypper refresh
zypper install python-icalendar
Para openSUSE Leap 15.0 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/server:Kolab:16.0/openSUSE_Leap_15.0/server:Kolab:16.0.repo
zypper refresh
zypper install python-icalendar
Para 15.3 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/server:Kolab:16.0/15.3/server:Kolab:16.0.repo
zypper refresh
zypper install python-icalendar