#TkInter file dialogs like open file, save, select folder, etc. are very easy, but ugly (actually sub-standard in terms of features) on Linux :(
#tkfiebrowser (https://tkfilebrowser.readthedocs.io/en/stable/) by Juliette Monsel, fixes this :D
...but this adds a project dependency and looks like it doesn't work on MacOS :(
#CustomTkinter doesn't have them at all :(
Do I want to hear about other options? Maybe. But I don't really want to make my students install another dependency and write more than a single line of code to open a file dialog, so I guess I'm out of luck.
Using #py5 (which they will have installed) it is more than a single line of code (which might be ok...), but it uses the #JavaSwing dialog infrastructure, I guess, that look quite ugly on Linux too... I'm really grumpy today.