code: function (url) {
      var req = new XMLHttpRequest();
  
      // Response handler. Check the console for errors.
      var respond = function () {
          if (req.status !== 200) {
            console.warn(req.responseText);
            return;
          }
          // Show the raw response text on page
          xmlOutput.textContent = req.responseText;
          // convert XML to javascript objects
          var json = sdmxmllib.mapSDMXMLResponse(req.responseText);
          // Convert to json and show on page
          jsonOutput.textContent = JSON.stringify(json, null, 2);
      };
  
      req.open('GET', url);
      // This will return latest version (SDMX-ML 2.1)
      req.setRequestHeader('Accept', 'application/xml');
  
      req.onreadystatechange = function () {
        if (req.readyState > 3) respond();
      };
  
      req.onerror = function (err) {
        console.warn(err);
      };
  
      req.send(null);
    }
docs: ------------------------------------------------------------------------------ Sends the request and handles response