/usr/lib/ is in ruby-active-model-serializers 0.9.3-1.
This file is owned by root:root, with mode 0o755.
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/usr/lib/ruby/
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/active_model_serializers.rb
/usr/lib/ruby/vendor_ruby/action_controller/
/usr/lib/ruby/vendor_ruby/action_controller/serialization_test_case.rb
/usr/lib/ruby/vendor_ruby/action_controller/serialization.rb
/usr/lib/ruby/vendor_ruby/active_model/
/usr/lib/ruby/vendor_ruby/active_model/serializable.rb
/usr/lib/ruby/vendor_ruby/active_model/serializer/
/usr/lib/ruby/vendor_ruby/active_model/serializer/railtie.rb
/usr/lib/ruby/vendor_ruby/active_model/serializer/version.rb
/usr/lib/ruby/vendor_ruby/active_model/serializer/generators/
/usr/lib/ruby/vendor_ruby/active_model/serializer/generators/resource_override.rb
/usr/lib/ruby/vendor_ruby/active_model/serializer/generators/serializer/
/usr/lib/ruby/vendor_ruby/active_model/serializer/generators/serializer/scaffold_controller_generator.rb
/usr/lib/ruby/vendor_ruby/active_model/serializer/generators/serializer/serializer_generator.rb
/usr/lib/ruby/vendor_ruby/active_model/serializer/generators/serializer/templates/
/usr/lib/ruby/vendor_ruby/active_model/serializer/generators/serializer/templates/controller.rb
/usr/lib/ruby/vendor_ruby/active_model/serializer/generators/serializer/templates/serializer.rb
/usr/lib/ruby/vendor_ruby/active_model/serializer/generators/serializer/USAGE
/usr/lib/ruby/vendor_ruby/active_model/serializer/config.rb
/usr/lib/ruby/vendor_ruby/active_model/serializer/association/
/usr/lib/ruby/vendor_ruby/active_model/serializer/association/has_one.rb
/usr/lib/ruby/vendor_ruby/active_model/serializer/association/has_many.rb
/usr/lib/ruby/vendor_ruby/active_model/serializer/association.rb
/usr/lib/ruby/vendor_ruby/active_model/serializer_support.rb
/usr/lib/ruby/vendor_ruby/active_model/default_serializer.rb
/usr/lib/ruby/vendor_ruby/active_model/array_serializer.rb
/usr/lib/ruby/vendor_ruby/active_model/serializable/
/usr/lib/ruby/vendor_ruby/active_model/serializable/utils.rb
/usr/lib/ruby/vendor_ruby/active_model/serializer.rb