I have the following code,

<?php
class Templater
{
    static $params = array();

    public static function assign($name, $value)
    {
        self::$params[] = array($name => $value);
    }

    public static function draw()
    {
        self::$params;
    }
}


 $test = Templater::assign('key', 'value');
 $test = Templater::draw();
 print_r($test);

How can I alter this script so I could use this?

$test = Templater::assign('key', 'value')->assign('key2', 'value2')->draw();
print_r($test);