> Basically, if something is just documented as being callable without > subclassing or instance checks being mentioned as supported in the > docs, it can be implemented as either a type or an ordinary function, > or pretty much any other kind of callable without being deemed an API > change So what would be your evaluation of http://docs.python.org/library/xml.etree.elementtree.html#xml.etree.ElementTree.Element in that respect? Regards, Martin