Get parent title in PyroCMS

page_parent.php

<?php defined('BASEPATH') OR exit('No direct script access allowed');

class Plugin_Page_Parent extends Plugin
{

    public function title()
    {
        // Use the URI to get the previous page name, and set the title accordingly

        $uri_parts = explode('/', $this->uri->uri_string());
        if (count($uri_parts) > 1)
        {
            $parent_slug = $uri_parts[count($uri_parts) - 2];
            $my_slug = end($uri_parts);

            // Find the parent page and get its title
            $this->load->model('pages/page_m');
            $parent = $this->page_m->get_by('slug', $parent_slug);
            $me = $this->page_m->get_by('slug', $my_slug);
            $this->template->title($parent->title, $me->title);
        }
    }
}