I have just extended the write-up of next weeks' assignment to include a discussion of the Project 1 code. 

You will probably find it useful for both this week's assignment and next week's assignment.

Here are the final paragraphs of the write-up.

Understanding the preceding may seem like a lot of work. It is. But that’s the sort of thing you must do when you are asked to use someone else’s code.

In your professional life, most of the software development work you will do will involve code that someone else has written—and that you will have to understand in order to do your job.

It’s important to develop the ability to take existing code and to understand it well enough to modify or extend it.