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/**
 * Change Image Alignment of Featured Image From Left to Right
 *
 */
function sk_change_image_alignment( $attributes ) {

	$attributes['class'] = str_replace( 'alignleft', 'alignright', $attributes['class'] );
		return $attributes;

}
add_filter( 'genesis_attr_entry-image', 'sk_change_image_alignment' );