On a Google Search, I found this article:
http://docs.python.org/release/1.4/lib/node201.html
Which showed examples of using the rect class, to perform union/intersections/checking if points are inside rect. Importing rect fails in Python 2.7. Is this class in another package?
I assume the question isn’t really “what happened to it?“, but “where can I find a class like this that I can use?“.
Most GUI libraries have a class like this. For example: wx.Rect, QRect/QRectF, gtk.gdk.Rectangle, PyGame rect.
If you want a generic rectangle class without the overhead of a GUI library, I think your only option is Sympy, which has a Geometry module that may suit your needs.
Finally, you may just choose to roll your own. It’s not very hard to make such a class.