Support for WooCommerce Shipment Tracking

functions.php

<?php
/**
  * @snippet       WooCommerce - Unifaun plugin by Redlight Media - Add Support for WooCommerce Shipment Tracking
  * @author        Redlight Media AB / Christopher Hedqvist
  * @compatible    WooCommerce 3.9.0
  */
add_action( 'ac_wc_unifaun_shipment_print_successful_print', 'redlight_postnord_add_tracking', 10, 3 );
function redlight_postnord_add_tracking($body, $response, $order){
  $provider = 'PostNord Sverige AB';
	if ( isset( $body->pdfs ) ) {
		foreach ( $body->parcels as $parcel ) {
			if ( function_exists( 'wc_st_add_tracking_number' ) ) {
                wc_st_add_tracking_number( $order->get_id(), $parcel->parcelNo, $provider);
            }
		}
	}
}