Code below has 1 major and 1 minor problem. Major issue is, once you push the button it visually stays pushed. Minor problem is, I run this in Cygwin. I've got an rxvt window behind the Tk window.

There’s a new and very detailed video tutorial about the Raspberry Pi available from the Australian firm Core Electronics. There are 30 videos and 5 chapters in total. A few of the introduction videos ...