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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 alertingNetToMs(Facility_presence=0, ProgressIndicator_presence=0, UserUser_presence=0):
 """ALERTING Section 9.3.1.1"""

    a = TpPd(pd=0x3)
    b = MessageType(mesType=0x1)  # 00000001
    packet = a / b
    if Facility_presence is 1:
        c = FacilityHdr(ieiF=0x1C)
        packet = packet / c
    if ProgressIndicator_presence is 1:
        d = ProgressIndicatorHdr(ieiPI=0x1E)
        packet = packet / d
    if UserUser_presence is 1:
        e = UserUserHdr(ieiUU=0x7E)
        packet = packet / e
    return packet