/usr/ is in ruby-multipart-post 1.2.0-2.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/
/usr/lib/ruby/
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/net/
/usr/lib/ruby/vendor_ruby/net/http/
/usr/lib/ruby/vendor_ruby/net/http/post/
/usr/lib/ruby/vendor_ruby/net/http/post/multipart.rb
/usr/lib/ruby/vendor_ruby/composite_io.rb
/usr/lib/ruby/vendor_ruby/parts.rb
/usr/lib/ruby/vendor_ruby/multipart_post.rb
/usr/lib/ruby/vendor_ruby/multipartable.rb
/usr/share/
/usr/share/doc/
/usr/share/doc/ruby-multipart-post/
/usr/share/doc/ruby-multipart-post/copyright
/usr/share/doc/ruby-multipart-post/changelog.Debian.gz
/usr/share/doc/ruby-multipart-post/README.txt
/usr/share/rubygems-integration/
/usr/share/rubygems-integration/all/
/usr/share/rubygems-integration/all/specifications/
/usr/share/rubygems-integration/all/specifications/multipart-post-1.2.0.gemspec