Made everything according the manual:
sudo apt-get install python-letsencrypt-apache
tried to uninstall and reinstall few times, tried to update python version, no luck…
there was a similar question without the answer: Can´t run letsencrypt as chron Job
as I understood this bug happens not so often, do not worry about that, I installed the GetSSL script.
Thank You for care and answer.
Regards
Sigitas