beaker-blog/src/templates/rss.xml

<?xml version="1.0" encoding="utf-8"?>
<rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom">

<channel>
    <title>Blog Title</title>
    <description>A short description of the blog.</description>
<language>en-us</language>
<link>localhost:5000/feed.xml</link>
<atom:link href="/feed.xml" rel="self" type="application/rss+xml" />

{% autoescape off %}
{{ content_string }}
{% endautoescape %}

</channel>
</rss>