Datablocks API

All,
I just finished writing a short article on the data blocks api for fastai v1. I know everyone is already talking about v2, but I did want to finish my basics first before I get to v2.
Here is the link : https://medium.com/@ndharap/data-pipelines-in-fastai-v1-4c927d7757d2

Feedback is welcome!

Nikhil