Add shortcode to list sites in WP Multisite

wp_multisite_shortcode_list_sites.php

function make_list_shortcode() {

    $subsites = get_sites(array('orderby' => 'registered', 'order' => 'DESC' ));

    if ( ! empty ( $subsites ) ) {

        $html = '<ul class="subsites">';

        foreach( $subsites as $subsite ) {

            $subsite_id = $subsite->blog_id;
            $subsite_name = get_blog_details( $subsite_id )->blogname;
            $subsite_link = get_blog_details( $subsite_id )->siteurl;
            $html .= '<li class="site-' . $subsite_id . '"><a href="' . $subsite_link . '" target="_blank">' . $subsite_name . '</a></li>';

        }

        $html .= '</ul>';
        return $html;

    }

}
add_shortcode('list_sites', 'make_list_shortcode');