Sphinxcontrib-proceduralimage is a project mainly written in Python, it's free.
embed pictures generated from python code into your sphinx documentation
This package adds the proceduralimage directive to Sphinx_.
.. _Sphinx: http://sphinx.pocoo.org/
It allows a python code snippet to be supplied, that generates an image, that will be included in the documentation.
It adds a single directive, proceduralimage. It takes a block of python
code, executes the code and extracts the local variables image_data and
alt. image_data will be saved to a .png in _images and embedded and
the alt variable will be used as the images alt tag.
The code is based almost entirely on sphinx.ext.graphviz.