Instead of pull request #95, I'd propose simplifying seealso directives. They already spit out normal admonitions, they can also become a normal admonition directive.
This changes behaviour subtly in a few cases. The latex builder now says “See also” instead of “See Also,” the text builder now handles indentation differently, the HTML builder is missing the admonition-see-also CSS class.
Right, thanks for the reminder! There are subtle changes in other builders as well (see my first post.) I, personally, am OK with these, considering that all other admonitions are handled like that (the sample after the change) in the text builder as well. If we do not like that, we should change it right in the text builder.
I didn't see any special cases in the original parser, but we should check against a larger corpus (say, the Python docs) if everything which has worked before continues to work properly.