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<?php $upgradeKeys = array( 'featured-listing', 'basic-pack', 'designer-blog', 'power-pack' ); $_upgradeKeys = array_diff( $upgradeKeys, array( 'featured-listing', 'basic-pack', 'designer-blog', 'power-pack' ) ); sort($_upgradeKeys); $upgradeKeys = $_upgradeKeys; $upgradeKeys[] = 'power-pack'; print_r($_upgradeKeys);

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