code: function _load(url) {
  
      var script = document.createElement('script'),
        done = false;
      script.src = url;
  
      // Once the script has been loaded remove the tag from the document.
      script.onload = script.onreadystatechange = function() {
        if ( !done && (!this.readyState || this.readyState === "loaded" || this.readyState === "complete") ) {
          done = true;
          script.onload = script.onreadystatechange = null;
          if ( script && script.parentNode ) {
            script.parentNode.removeChild( script );
          }
        }
      };
  
      if ( !head ) {
        head = document.getElementsByTagName('head')[0];
      }
  
      // Actually load script.
      head.appendChild( script );
    }
docs: Making the request is as simple as appending a new script tag to the document. The URL has the *callback* parameter with the function that will be called with the response data.