For SLES15SP3 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:orcharhino:sles_15/SLES15SP3/home:orcharhino:sles_15.repo
zypper refresh
zypper install python-ethtool
For SLES15SP2 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:orcharhino:sles_15/SLES15SP2/home:orcharhino:sles_15.repo
zypper refresh
zypper install python-ethtool
For SLES15SP1 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:orcharhino:sles_15/SLES15SP1/home:orcharhino:sles_15.repo
zypper refresh
zypper install python-ethtool