code: public static HtmlTree MAIN(Content body) {
          HtmlTree htmltree = new HtmlTree(HtmlTag.MAIN, nullCheck(body));
          htmltree.setRole(Role.MAIN);
          return htmltree;
      }
docs: Generates a MAIN tag with role attribute and some content.
  
  @param body content of the MAIN tag
  @return an HtmlTree object for the MAIN tag