Hi Raymond,

About the C API, I wanted to know that because I started to use neovim
for the development of CPython mix between C and Python is really great
with this tool. Also, I wanted to have the description of the C parts,
example, when I have PyArg_ParseTupleAndKeywords under the cursor, with
(n)vim I could use the K shortcut and see the description of this
function via the keywordprg of vim.

But we have the result from Sphinx, because the C part is described in
the .rst files. So, maybe I could develop a wrapper for Sphinx and the
manpages.

So, thank you for your PR.