PHPCMS 如何添加模块？

<?php
    defined('IN_PHPCMS') or exit('No permission resources.');
    class mytest
    {
        function __construct(){}
        public function init()
        {
            $myvar = 'hello world!';
            echo $myvar;
        }
        public function mylist()
        {
            $myvar = 'hello world! This is an example!';
            echo $myvar;
        }
    }
?>

public function init()
{
    $myvar = 'hello world!';
    echo $myvar;
    include template('test', 'index');
}

public function init()
{
    $myvar = 'oh,i am phpcmser';
    echo $myvar;
    include $this->admin_tpl('mytest_admin_list');
}

<?php
defined('IN_PHPCMS') or exit('No permission resources.');
pc_base::load_sys_class('model', '', 0);
class test_model extends model
{
    public function __construct()
    {
        $this->db_config = pc_base::load_config('database');
        $this->db_setting = 'default';
        $this->table_name = 'test';
        parent::__construct();
    }
 }
?>