<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def frequencyRedefinition(CellChannelDescription_presence=0):
 """Frequency redefinition Section 9.1.13"""

    a = TpPd(pd=0x6)
    b = MessageType(mesType=0x14)  # 00010100
    c = ChannelDescription()
    d = MobileAllocation()
    e = StartingTime()
    packet = a / b / c / d / e
    if CellChannelDescription_presence is 1:
        f = CellChannelDescriptionHdr(ieiCCD=0x62, eightBitCCD=0x0)
        packet = packet / f
    return packet