Graded Homework 2

#### Grade: 5/5

Excellent work, Sarah! The work was impressive to say the least. Great way to generalize for `grid.py`!

Once you've read the comments, make a comment to the pull request or send me/Diana an email, letting us know that you've checked them out. Afterwards, close the PR (and optionally delete the graded branch)

#### REMEMBER NOT TO MERGE THESE PRs!