The main solutions manual is solutions.tex.
Some solutions have figures, which are done directly in LaTeX using the TikZ and PGFPLOTS packages.
The python directory contains some quick and dirty Python scripts that were used to gain insight while working on some of the exercises.
These are not documented at all and so probably will not be of interest to anyone else.
When doing exercises it can be useful to see a list of lemmas that have been written as part of the solutions.
Running the lemmas.py Python script will build lemmas_content.tex that contains these lemmas.
You can then build a lemma list document by compiling lemmas.tex, which includes lemmas_content.tex.
Please submit an issue if you discover any errors in any of the proofs or any typos.
For an up-to-date PDF of the solutions manual and links to other resources for this text head over to my website. Note that this is still a work in progress.