code: def clear(self) -> None:
          
          self._headers = httputil.HTTPHeaders(
              {
                  "Server": "TornadoServer/%s" % tornado.version,
                  "Content-Type": "text/html; charset=UTF-8",
                  "Date": httputil.format_timestamp(time.time()),
              }
          )
          self.set_default_headers()
          self._write_buffer = []  # type: List[bytes]
          self._status_code = 200
          self._reason = httputil.responses[200]
docs: Resets all headers and content for this response.