One of the many pieces of the python.org “family” is a feed aggregator: Planet Python. It’s been running for years either as planetpython.org or planet.python.org (the latter now redirects to the former). Naturally, over the years, some of the blogs it aggregates have disappeared. But it can also happen that the feed URL changes because of a change of blog engine, a new domain, a switch to https etc.
These days, the Planet configuration is maintained on Github and you can either submit a Pull Request or just email the Planet team. We probably add two or three new blogs every month and tweak a couple more (new URLs etc.)
So… please check the Planet config file or look down the left-hand side of Planet Python and, if your blog is listed but is now dead, please send us a PR or an email. Likewise if the blog is still alive but at a different address, please do the same. After a time, we’ll run a cull of Blogs which consistently return 404 and thin our list down.
Of course, please also ping us if you’d like to add your blog. Easiest way is to open an issue or raise a PR which will use Github’s recently-added issue template mechanism to make sure you’ve got everything lined up.