code: def activatePdpContextRequest(AccessPointName_presence=0,
                                ProtocolConfigurationOptions_presence=0):
      
      a = TpPd(pd=0x8)
      b = MessageType(mesType=0x41)  # 01000001
      c = NetworkServiceAccessPointIdentifier()
      d = LlcServiceAccessPointIdentifier()
      e = QualityOfService()
      f = PacketDataProtocolAddress()
      packet = a / b / c / d / e / f
      if AccessPointName_presence is 1:
          g = AccessPointName(ieiAPN=0x28)
          packet = packet / g
      if ProtocolConfigurationOptions_presence is 1:
          h = ProtocolConfigurationOptions(ieiPCO=0x27)
          packet = packet / h
      return packet
docs: ACTIVATE PDP CONTEXT REQUEST Section 9.5.1