ref: 40f6e00b9c4b0f5bdca1cc7caf27af23a6b10786 dir: /sys/lib/python/mercurial/templates/rss/header.tmpl/
<?xml version="1.0" encoding="{encoding}"?> <rss version="2.0"> <channel> <link>{urlbase}{url}</link> <language>en-us</language>