Creating or updating the music21 documentation requires a few additional programs to be installed, most importantly one called Sphinx. Sphinx is a documentation generator that uses reStructuredText (rst) as its markup language and outputs HTML documents.
1) Install pip
In order to get additional modules, you’ll need a way of getting them more easily. The easiest way to do this is to get pip (or pip3 for Python3). Just go to https://pip.pypa.io/ and they’ll help you out.
2) Downloading and Installing Sphinx
Once pip is installed simply run: “sudo pip install sphinx”
3) Install pandoc
You can get pandoc (the universial documentation converter) at: http://pandoc.org/installing.html
4) Run documentation/make.py
Find the documentation folder within music21. And run with python or python3 the make.py file, which will automatically build all the music modules in music21 into the “autogenerated” folder and from there into the “build/html” folder.