code: function(options) {
          var doc;
          if (window.ActiveXObject) {
              doc = new ActiveXObject("Microsoft.XMLDOM");
              this.xmldom = doc;
          } else {
              doc = document.implementation.createDocument("", "", null);
          }
          var node = this.writeNode("wps:Execute", options, doc);
          this.setAttributeNS(
              node, this.namespaces.xsi,
              "xsi:schemaLocation", this.schemaLocation
          );
          return OpenLayers.Format.XML.prototype.write.apply(this, [node]);
      }
docs: Constructor: OpenLayers.Format.WPSExecute
  
  Parameters:
  options - {Object} An optional object whose properties will be set on
  this instance.
   
  Method: write
  
  Parameters:
  options - {Object} Optional object.
  
  Returns:
  {String} An WPS Execute request XML string.