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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 detachRequest(GmmCause_presence=0):
 """DETACH REQUEST Section 9.4.5"""

    a = TpPd(pd=0x3)
    b = MessageType(mesType=0x5)  # 00000101
    c = DetachTypeAndForceToStandby()
    packet = a / b / c
    if GmmCause_presence is 1:
        e = GmmCause(ieiGC=0x25)
        packet = packet / e
    return packet