Include a text file *as is* in (Python) Sphinx Docs
The correct answer is the :download:
role.
Cf: Georg's answer on the Sphinx Mailing List
I think you can include an external document fragment, as described here:
http://docutils.sourceforge.net/docs/ref/rst/directives.html#including-an-external-document-fragment
From that text, something like this should do it:
.. include:: inclusion.txt
:literal: