code: def send_header(self, keyword, value):
          
          if self.request_version != 'HTTP/0.9':
              self.wfile.write("%s: %s\r\n" % (keyword, value))
  
          if keyword.lower() == 'connection':
              if value.lower() == 'close':
                  self.close_connection = 1
              elif value.lower() == 'keep-alive':
                  self.close_connection = 0
docs: Send a MIME header.