Thanks for the feedback, guys.
It's not so much what's great about IDLE as what's not great about the CMD box, e.g. Fixed width window, no colour coding, plus I can copy/paste code from my text editor into the CMD box, but not vice versa. I make a lot of errors (I suspect you make rather less
) it takes me a while to get things working.
Nevertheless you've given me an idea. My text editor, Notepad++, has a Console plugin. This might be the answer.
My current area of interest is the Container class used in Polish, plus the versions in Modify Epub and the KoboTouchExtended driver. I'm not sure which I should consider the 'master' version.
A couple of years ago I created something for myself which could read/store data from a single selected epub (either in the calibre database or just a .epub on disk) so that I could do 'updating stuff'. It never occurred to me that I'd cobbled together a 'container' of sorts, different data structures of course. Modify Epub now does some of those update things (rather better than I was doing them), but I still have a daily requirement for other personal epub updating. I thought maybe it was time to try using an official calibre epub container.