/usr/lib/ is in ruby-gobject-introspection 2.2.5-4build1.
This file is owned by root:root, with mode 0o755.
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/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/ruby/
/usr/lib/x86_64-linux-gnu/ruby/vendor_ruby/
/usr/lib/x86_64-linux-gnu/ruby/vendor_ruby/2.3.0/
/usr/lib/x86_64-linux-gnu/ruby/vendor_ruby/2.3.0/gobject_introspection.so
/usr/lib/ruby/
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/gobject-introspection.rb
/usr/lib/ruby/vendor_ruby/gobject-introspection/
/usr/lib/ruby/vendor_ruby/gobject-introspection/boxed-info.rb
/usr/lib/ruby/vendor_ruby/gobject-introspection/object-info.rb
/usr/lib/ruby/vendor_ruby/gobject-introspection/interface-info.rb
/usr/lib/ruby/vendor_ruby/gobject-introspection/loader.rb
/usr/lib/ruby/vendor_ruby/gobject-introspection/callable-info.rb
/usr/lib/ruby/vendor_ruby/gobject-introspection/collection-reader.rb
/usr/lib/ruby/vendor_ruby/gobject-introspection/repository.rb
/usr/lib/ruby/vendor_ruby/gobject-introspection/struct-info.rb
/usr/lib/ruby/vendor_ruby/gobject-introspection/union-info.rb