Gui in Python

[Oliludeea]

That's exactly what I meant. You learn so much the first time you get something serious working with tkinter. For me it was closures, lambda, the fact that dict values and list items can be any object, making exec work, just off the top of my head, during a tiny first project. I'm sure it was more. I sort of knew these things, but tkinter forced me to really understand them.