Add explanation re: code example

[benkoshy]

#219

This PR seeks to clarify any queries that other readers may have re: the above code.

I hope it is helpful to you. Thanking @fdbeirao for the contents of this commit.

regards Ben

So the kind of PRs that are practical to handle include:

• Fixing misspellings
• Fixing broken links
• Fixing typos in code

Make your PR as small as possible.

Reviewing a typo is easy. Reviewing 10 typos is hard because 9 may be good. Now there is a bigger coordination overhead.