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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 ccEstablishment():
 """CC-ESTABLISHMENT Section 9.3.17a"""

    a = TpPd(pd=0x3)
    b = MessageType(mesType=0x4)  # 00000100
    c = SetupContainer()
    packet = a / b / c
    return packet