gistfile1.txt

function pc_show_parents_cb( $atts ) {
	$atts = shortcode_atts( array(
		'slug' => '',
		'child' => '',
		'link' => 'true'
	), $atts, 'bartag' );

	if( empty( $atts['slug'] ) ) {
		return '';
	}
	
	if( empty ( $atts['child'] ) ) {
		$atts['child'] = get_the_ID();
	}

	$plm = new SP_Premium_Post_Link_Manager();
	ob_start();
	$plm->generate_parents_list( $atts['slug'], $atts['child'], $atts['link'], false );
	return ob_get_clean();
}
add_shortcode( 'pc_show_parents', 'pc_show_parents_cb' );