As I anticipated, I started this series on how to use TensorFlow for solving the Advent of Code 2021 puzzles.
In this article, I show how to use Python enums in TensorFlow (the limitation that we face, since we can only use TensorFlow-compatible data-types), how the type annotations for TensorFlow programs are limited, and also briefly introduce the DeepMind project TensorAnnotations.
I solved the puzzle too 
The day 2 challenge was very similar to the challenge of day 1, but I already solved the challenges for days 3 and 4 and they are way more interesting.
So two new articles will come soon!