/usr/share/doc/ruby2.0-tcltk/changelog.Debian.gz is in ruby2.0-tcltk 2.0.0.484-1ubuntu2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/ruby2.0-tcltk/../libruby2.0/changelog.Debian.gz
/usr/share/doc/ruby2.0-tcltk/../libruby2.0/changelog.Debian.gz