Notes:
- Be sure that your modified notebook file has the EXACT SAME NAME as the original when you commit, or your autograding checks will fail!
- Be sure that ALL NECESSARY CODE for each task is contained in the single cell for that task. The code will be run in isolation, so it needs to be able to stand alone. You can test this by resetting the kernel for your notebook, and then running that single cell. If it runs as expected, then you're good to go!