/usr/ is in ruby-systemu 2.6.5-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/rubygems-integration/all/
/usr/lib/
/usr/lib/ruby/
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/systemu.rb
/usr/share/
/usr/share/rubygems-integration/
/usr/share/rubygems-integration/all/specifications/
/usr/share/rubygems-integration/all/specifications/systemu-2.6.5.gemspec
/usr/share/doc/
/usr/share/doc/ruby-systemu/
/usr/share/doc/ruby-systemu/README
/usr/share/doc/ruby-systemu/changelog.Debian.gz
/usr/share/doc/ruby-systemu/examples/
/usr/share/doc/ruby-systemu/examples/b.rb
/usr/share/doc/ruby-systemu/examples/f.rb
/usr/share/doc/ruby-systemu/examples/d.rb
/usr/share/doc/ruby-systemu/examples/c.rb
/usr/share/doc/ruby-systemu/examples/a.rb
/usr/share/doc/ruby-systemu/examples/e.rb
/usr/share/doc/ruby-systemu/copyright