docs: def RequestPacket(self):
          """Create a ready-to-transmit authentication request packet.
          Return a RADIUS packet which can be directly transmitted
          to a RADIUS server.
  
          :return: raw packet
          :rtype:  string
          """
          attr = self._PktEncodeAttributes()
  
          if self.authenticator is None:
              self.authenticator = self.CreateAuthenticator()
  
          if self.id is None:
              self.id = self.CreateID()
  
          header = struct.pack('!BBH16s', self.code, self.id,
              (20 + len(attr)), self.authenticator)
  
          return header + attr