static int mxf_is_partition_pack_key(UID key)
{
    //NOTE: this is a little lax since it doesn't constraint key[14]
    return !memcmp(key, mxf_header_partition_pack_key, 13) &&
            key[13] >= 2 && key[13] <= 4;
}
static int mxf_is_partition_pack_key(UID key)
{
     
    return !memcmp(key, mxf_header_partition_pack_key, 13) &&
            key[13] >= 2 && key[13] <= 4;
}