code: def start_response(self, status = 200, headers = [], clearheaders = True, disabletransferencoding = False):
          "Start to send response"
          if self._sendHeaders:
              raise HttpProtocolException('Cannot modify response, headers already sent')
          self.status = status
          self.disabledeflate = disabletransferencoding
          if clearheaders:
              self.sent_headers = headers[:]
          else:
              self.sent_headers.extend(headersf start_response(self, status = 200, headers = [], clearheaders = True, disabletransferencoding = False):
          "Start to send response"
          if self._sendHeaders:
              raise HttpProtocolException('Cannot modify response, headers already sent')
          self.status = status
          self.disabledeflate = disabletransferencoding
          if clearheaders:
              self.sent_headers = headers[:]
          else:
              self.sent_headers.extend(headers)
docs: Start to send response