https://bugzilla.wikimedia.org/show_bug.cgi?id=72047
--- Comment #18 from Fabian CommodoreFabianus@gmx.de --- Hmmm about the interwiki problem: It doesn't really matter why it does also parse interwiki links (*) because otherwise we would just hide a potential bug.
Could you execute the following line in shell:
pywikibot.Site('cs', 'wikipedia').interwiki('outreach')
This returns for me 'Site("outreach", "outreach")'.
*: There is no reliable way to know if a link is an interwiki link or not without looking into the prefix. The script just goes the extra mile to also assign a Site object to it which could be ignored but that must be done by the script by catching the exception.