Yes. In my opinion basic Python is the only "almost requisite". The book does a very good job at hand holding, it really helps to know a little Python (which the book also caters for). My advice is follow along with the book. If you get stuck by any Python stuff. Take a minute out of web2py and just solve that issue with Python (at the command line interpreter or with one of the many excellent shells, e.g. IDLE), then go back. Pretty soon you'll feel incredibly productive :-)
There's a lot to web development, but the best way is to go and find out as you feel the need, otherwise you will soon feel overwhelmed.
