/usr/lib/ruby/ is in ruby-awesome-nested-set 3.0.0-1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/awesome_nested_set.rb
/usr/lib/ruby/vendor_ruby/awesome_nested_set/
/usr/lib/ruby/vendor_ruby/awesome_nested_set/tree.rb
/usr/lib/ruby/vendor_ruby/awesome_nested_set/iterator.rb
/usr/lib/ruby/vendor_ruby/awesome_nested_set/awesome_nested_set.rb
/usr/lib/ruby/vendor_ruby/awesome_nested_set/model.rb
/usr/lib/ruby/vendor_ruby/awesome_nested_set/helper.rb
/usr/lib/ruby/vendor_ruby/awesome_nested_set/version.rb
/usr/lib/ruby/vendor_ruby/awesome_nested_set/columns.rb
/usr/lib/ruby/vendor_ruby/awesome_nested_set/model/
/usr/lib/ruby/vendor_ruby/awesome_nested_set/model/rebuildable.rb
/usr/lib/ruby/vendor_ruby/awesome_nested_set/model/relatable.rb
/usr/lib/ruby/vendor_ruby/awesome_nested_set/model/movable.rb
/usr/lib/ruby/vendor_ruby/awesome_nested_set/model/prunable.rb
/usr/lib/ruby/vendor_ruby/awesome_nested_set/model/transactable.rb
/usr/lib/ruby/vendor_ruby/awesome_nested_set/model/validatable.rb
/usr/lib/ruby/vendor_ruby/awesome_nested_set/set_validator.rb
/usr/lib/ruby/vendor_ruby/awesome_nested_set/move.rb