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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 to_full_uuid (uuid):
 """ converts a short 16-bit or 32-bit reserved UUID to a full 128-bit Bluetooth UUID. """

    if not is_valid_uuid (uuid): raise ValueError ("invalid UUID")
    if len (uuid) == 4:
        return "0000%s-0000-1000-8000-00805F9B34FB" % uuid
    elif len (uuid) == 8:
        return "%s-0000-1000-8000-00805F9B34FB" % uuid
    else:
        return uuid