This widget is intended for applications where the set of
content pages is static, or at least grows only at the
end. If there is a need for a widget to display a dynamically
changing set of pages, new external methods will be required to
support page insertion and deletion at arbitrary locations in the
list of content pages. A particularly Pythonic way to do that
might be to mimic the methods on list types such as
In any event, the addition of such features will require a serious rethinking of the internal attributes that manage the content pages.