Here, you might lay out the reasons behind writing this code. You can link to specs, issues, or bugs in order to give someone a better idea of how a decision was made. This is your chance to give context to your reviewer. Ego depletion - the idea that willpower is used up over time - can be easily applied to your reviewer. We are human, after all. You'll likely get one shot at a quality review, so help your reviewer help you. Flush out this section.
How did you test this code? Did you write a unit test, or test it manually? Can you provide an animated gif or a screenshot to demonstrate your code does what it purports to do? What about test output or a useful snippet from a logfile? Help show that your code works.
Is there some part of the code that you know probably doesn't work as it should? Call out potential weak spots, and get help addressing them.