Looking at the docs and the comments it would seem that py:layout and
py:slot do not offer much over the existing py:match/py:def, and may
muddy the waters somewhat (people take a while to understand how to use
py:match and these extra tags may add to the confusion). I don't like
the layout_params variable in there, I think you can just do for
example:
<?python self.page_title = "Welcome"?>
in your page template, and in master template for example:
<title>${page_title}</title>
So until I see some compelling case for py:layout I think I stick to
py:match for now.
Thanks for the advice !