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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 __create_tcp_top(self, packet):
 """ witch the complete packet set top header """

        length = len(packet)
        top = pack('<HHI', const.MACHINE_PREPARE_DATA_1, const.MACHINE_PREPARE_DATA_2, length)
        return top + packet