I currently have the budget to buy an intermediate to advanced python. The books price has to be below $50 (Canada), if possible, unless it's a really good book.

Preferably there should be GUI programming in the book (not TK or QT, GTK or other toolsets preferred). Network programming (Socket) would be nice.

The flavor of python that I want to go in depth is CPython, and the version is Python 2 (If I was interested in learning python 3 i would of gone to dive into python 3)

What is a good book that meets all that? Again, I only have $50 to spend so I want to make it a good one.

Please do not recommend Dive into python or think python as i have read both of them. Free books would be nice, especially if they are available in html format