Some points you should note:
This book covers the new-style objects (introduced a long time ago in Python 2.2). Examples are valid for Python 2.5 and all the way to Python 3.x.
This book is not for absolute beginners. It is for people who already know Python (even a little Python) and want to know more.
This book provides a background essential for grasping new-style attribute access and other mechanisms (descriptors, properties and the like). If you are interested in only attribute access, you could go straight to Python Attributes and Methods, after verifying that you understand the Summary of this book.