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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def immediateAssignmentExtended(StartingTime_presence=0):
 """IMMEDIATE ASSIGNMENT EXTENDED Section 9.1.19"""

    a = L2PseudoLength()
    b = TpPd(pd=0x6)
    c = MessageType(mesType=0x39)  # 00111001
    d = PageModeAndSpareHalfOctets()
    f = ChannelDescription()
    g = RequestReference()
    h = TimingAdvance()
    i = MobileAllocation()
    packet = a / b / c / d / f / g / h / i
    if StartingTime_presence is 1:
        j = StartingTimeHdr(ieiST=0x7C, eightBitST=0x0)
        packet = packet / j
    k = IaxRestOctets()
    packet = packet / k
    return packet