It makes pictures that look like this:
Note: the original implementation doesn't really support any aliases or functions that you may have for git functionality, which means it's probably not very helpful in its current state.
mktmpenv -n
pip install -r requirements.local.txt
history | python git-workflow.py > graph.svg
deactivate
# Open the SVG file in a web browser with `open .` and then
# right-clicking the file and choosing Open With > Google Chrome