I copied the GUI creation from my personal text editor. The scrollbar and stretchability could have been left out, for sure. You're only seeing a portion of a more complex GUI.
After writing several Tkinter applications, I decided that subclassing without a clear reason only had the effect of polluting the namespace of my class. I like seeing only my attributes and methods during code completion. Thanks for your interest and help. -- https://mail.python.org/mailman/listinfo/python-list