# File lib/action_view/helpers/form_tag_helper.rb, line 456
      def field_set_tag(legend = nil, options = nil, &block)
        content = capture(&block)
        output = tag(:fieldset, options, true)
        output.safe_concat(content_tag(:legend, legend)) unless legend.blank?
        output.concat(content)
        output.safe_concat("</fieldset>")
      end