Some small fixes

Good afternoon, my friend!

First of all, I want to say thanks to you for this greate book. I think it is a good book for those who are looking for a beginner's tutorial for Python. 

It is about two or there years ago, I think, when I first heard of this book. At that time, I'am not able to read some book in English yet, so I got a chinese translation, which takes me into the gate of Python programming.

Recently, I reread this book. This time, of course, the english version. I couldn't believe that I can read the whole book without my dictionary at hand. Of course, it all dues to your effort for make this book an easy-to-understand one.

When I was reading this book, I found several places in the book may omit one or two space characteres. So I try to fix them. Hope my work will be useful.

At last thanks again for creating this book and sharing it for free. Best wishes!