Trafikverket Weatherstation

I’m trying to activate Trafikverket Weatherstation. Added configuration but ‘Check config’ gives the following error:
2020-07-13 19:52:17 ERROR (SyncWorker_18) [homeassistant.util.package] Unable to install package pytrafikverket==0.1.5.9: Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-install-w1op8e5y/lxml/

Running Home Assistant 0.103.5 on RP4

Any ideas what to do?