https://runestone.academy/runestone/books/published/thinkcspy/GUIandEventDrivenProgramming/toctree.html
https://www.youtube.com/watch?v=D8-snVfekto
https://www.youtube.com/watch?v=yQSEXcf6s2I&list=PLCC34OHNcOtoC6GglhF3ncJ5rLwQrLGnV
https://stackoverflow.com/questions/14142194/is-there-a-gui-design-app-for-the-tkinter-grid-geometry
Visual Tkinter
http://visualtkinter.sourceforge.net/download.htm