Para 15.6 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/devel:languages:python:backports/15.6/devel:languages:python:backports.repo
zypper refresh
zypper install python-truststore
Para 15.5 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/devel:languages:python:backports/15.5/devel:languages:python:backports.repo
zypper refresh
zypper install python-truststore
Para 15.4 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/devel:languages:python:backports/15.4/devel:languages:python:backports.repo
zypper refresh
zypper install python-truststore