Georgios Fragkoulidis

First of all, kudos to @molinav for keeping basemap alive. I still find it nicer than Cartopy. Earlier python versions give a _FutureWarning_ and newer python versions an _IndexError_ on...

### What happened? With the previous version we could set options that are not always needed (like 'pressure_level' and 'leadtime_month') to "None". This was really helpful as it allowed us...