# File lib/mime/types.rb, line 522
    def to_hash
      { 'Content-Type'              => @content_type,
        'Content-Transfer-Encoding' => @encoding,
        'Extensions'                => @extensions,
        'System'                    => @system,
        'Obsolete'                  => @obsolete,
        'Docs'                      => @docs,
        'URL'                       => @url,
        'Registered'                => registered?,
      }
    end