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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 _unpack_sdp_into_packet(packet, bytestring):
 """Unpack the SDP header from a bytestring into a packet. Parameters packet : :py:class:`.SDPPacket` Packet into which to store the unpacked header. bytestring : bytes Bytes from which to unpack the header data. """

    # Extract the header and the data from the packet
    packet.data = bytestring[10:]  # Everything but the header

    # Unpack the header
    (flags, packet.tag, dest_cpu_port, src_cpu_port,
     packet.dest_y, packet.dest_x,
     packet.src_y, packet.src_x) = struct.unpack_from('<2x8B', bytestring)
    packet.reply_expected = flags == FLAG_REPLY

    # Neaten up the combined VCPU and port fields
    packet.dest_cpu = dest_cpu_port & 0x1f
    packet.dest_port = (dest_cpu_port >> 5)  # & 0x07
    packet.src_cpu = src_cpu_port & 0x1f
    packet.src_port = (src_cpu_port >> 5)