docs: def queryset_formatter(queryset):
      """
      This is used for custom detail fields returning a QuerySet of
      admin objects.
      """
      return Markup(
          base_list_formatter(
              None,
              [
                  '<a href="{}">{}</a>'.format(u.get_admin_url(_external=True), u)
                  for u in queryset
              ],
          )
      )