Some of this week's topics are covered in Think Python:
14.9 Writing modules
And in Introducing Python:
Chapter 11. Modules, Packages, and Goodies
Modules and the import Statement
Packages
For learning pygame, I recommend the book Making Games with Python & Pygame. You can read it online, or download a PDF copy for free.
Don't forget that we have a pygame quick reference page that is linked from the course home page.
Here are the pygame examples we saw in the lecture: