code: def convert(self, request, response, data):
          
  
          qstr = request.query_string
  
          return self.escape('?%s' % qstr) if qstr else ''
docs: Performs the desired Conversion.
  
          :param request: The webob Request object describing the
                          request.
          :param response: The webob Response object describing the
                           response.
          :param data: The data dictionary returned by the prepare()
                       method.
  
          :returns: A string, the results of which are the desired
                    conversion.