code: def _fetch(self, uri, sub_domain=False):
          
          url = self._build_request_url(uri, sub_domain=sub_domain)
  
          try:
              res = self.request_handler.send("HEAD", url=url, allow_redirects=self.follow_redirects)
              if res.status_code not in self.ignored_error_codes:
                  self._log_response(res.status_code, url, res.headers)
          except (AttributeError, RequestHandlerException):
              # res is None or another error occurred
              pass
docs: Send a HEAD request to URL and print response code if it's not in ignored_error_codes
          :param uri: URI to fuzz
          :param sub_domain: If True, build destination URL with {URL}.{HOST} else {HOST}/{URL}