code: function(features) {
          if(!(OpenLayers.Util.isArray(features))) {
              features = [features];
          }
          var kml = this.createElementNS(this.kmlns, "kml");
          var folder = this.createFolderXML();
          for(var i=0, len=features.length; i<len; ++i) {
              folder.appendChild(this.createPlacemarkXML(features[i]));
          }
          kml.appendChild(folder);
          return OpenLayers.Format.XML.prototype.write.apply(this, [kml]);
      }
docs: APIMethod: write
  Accept Feature Collection, and return a string.
  
  Parameters:
  features - {Array(<OpenLayers.Feature.Vector>)} An array of features.
  
  Returns:
  {String} A KML string.