Para openSUSE Tumbleweed execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/devel:languages:perl:CPAN-C/openSUSE_Tumbleweed/devel:languages:perl:CPAN-C.repo
zypper refresh
zypper install perl-Class-ISA
Para 15.5 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/devel:languages:perl:CPAN-C/15.5/devel:languages:perl:CPAN-C.repo
zypper refresh
zypper install perl-Class-ISA
Para 15.4 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/devel:languages:perl:CPAN-C/15.4/devel:languages:perl:CPAN-C.repo
zypper refresh
zypper install perl-Class-ISA