function externalLinks() { 
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          var anchors = document.getElementsByTagName("a"); 
          for (var i=0;i<anchors.length;i++) { 
            var anchor = anchors[i]; 
            if (anchor.getAttribute("href") && anchor.getAttribute("rel") == "external") 
            anchor.target = "_blank"; 
          } 
      } 
    window.onload = externalLinks;