/usr/lib/mime/packages/mime-support is in mime-support 3.54ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | application/x-debian-package; /usr/lib/mime/debian-view %s; needsterminal; description=Debian GNU/Linux Package; nametemplate=%s.deb; priority=0
#audio/basic; /usr/lib/mime/playaudio %s; description=Basic uLaw Audio; nametemplate=%s.au; priority=0
|