code: func (r *Response) flush() {
  	if r._skipFlush {
  		log.Debug("Already sent. Skipping flushing")
  		return
  	}
  
  	// set all cookies to response object
  	for k, v := range r.Cookie {
  		log.Debug(k)
  		http.SetCookie(r.writer, v)
  	}
  
  	// in case of file call separate function for piping file to client
  	if len(r.file) > 0 {
  		log.Debugf("found file, sending")
  		r.sendFile()
  	} else if len(r.redirect) > 0 {
  		http.Redirect(r.writer, r.request, r.redirect, r.Status)
  	} else {
  		r.writer.WriteHeader(r.Status)
  		r.writer.Write(r.data)
  	}
  }
docs: // Write result to ResponseWriter.