code: def routingAreaUpdateAccept(PTmsiSignature_presence=0,
                              MobileId_presence=0, MobileId_presence1=0,
                              ReceiveNpduNumbersList_presence=0,
                              GprsTimer_presence=0, GmmCause_presence=0):
      
      a = TpPd(pd=0x3)
      b = MessageType(mesType=0x9)  # 00001001
      c = ForceToStandbyAndUpdateResult()
      e = GprsTimer()
      f = RoutingAreaIdentification()
      packet = a / b / c / e / f
      if PTmsiSignature_presence is 1:
          g = PTmsiSignature(ieiPTS=0x19)
          packet = packet / g
      if MobileId_presence is 1:
          h = MobileIdHdr(ieiMI=0x18, eightBitMI=0x0)
          packet = packet / h
      if MobileId_presence1 is 1:
          i = MobileIdHdr(ieiMI=0x23, eightBitMI=0x0)
          packet = packet / i
      if ReceiveNpduNumbersList_presence is 1:
          j = ReceiveNpduNumbersList(ieiRNNL=0x26)
          packet = packet / j
      if GprsTimer_presence is 1:
          k = GprsTimer(ieiGT=0x17)
          packet = packet / k
      if GmmCause_presence is 1:
          l = GmmCause(ieiGC=0x25)
          packet = packet / l
      return packet
docs: ROUTING AREA UPDATE ACCEPT Section 9.4.15