code: def options(self, request, response):
          
          # Gather a list available HTTP/1.1 methods for this URI.
          response['Allowed'] = ', '.join(self.meta.http_allowed_methods)
  
          # All CORS handling is done for every HTTP/1.1 method.
          # No more handling is neccesary; set the response to 200 and return.
          response.status = http.client.OK
docs: Process an `OPTIONS` request.
  
          Used to initiate a cross-origin request. All handling specific to
          CORS requests is done on every request however this method also
          returns a list of available methods.