Why dose sort code do this please ??

Sorry not very good with code ,where do I put this in ,I think this is the problem

update_option(‘su_compatibility_mode_prefix’, ‘gn_’);

But not sure where it must go ?

<?php

define( ‘DYNAMIK_ACTIVE’, true );

/* Call Catalyst’s core functions */
require_once( TEMPLATEPATH . ‘/lib/catalyse.php’ );

/* Call Dynamik’s functions */
if( file_exists( TEMPLATEPATH . ‘/lib/functions/catalyst-dynamik-functions.php’ ) )
{
require_once( TEMPLATEPATH . ‘/lib/functions/catalyst-dynamik-functions.php’ );
}

Thank Man ,very much ..