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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 get_next_slip(raw):
 """ Get the next slip packet from raw data. Returns the extracted packet plus the raw data with the remaining data stream. """

    if not is_slip(raw):
        return None, raw
    length = raw[1:].index(SLIP_END)
    slip_packet = decode(raw[1:length+1])
    new_raw = raw[length+2:]
    return slip_packet, new_raw