public function toArrayAfter( $arr ) {

		$product             = $this->get_product();
		$arr['access_plans'] = array();
		foreach ( $product->get_access_plans( false, false ) as $p ) {
			$arr['access_plans'][] = $p->toArray();
		}

		$arr['sections'] = array();
		foreach ( $this->get_sections() as $s ) {
			$arr['sections'][] = $s->toArray();
		}

		$arr['categories'] = $this->get_categories(
			array(
				'fields' => 'names',
			)
		);
		$arr['tags']       = $this->get_tags(
			array(
				'fields' => 'names',
			)
		);
		$arr['tracks']     = $this->get_tracks(
			array(
				'fields' => 'names',
			)
		);

		$arr['difficulty'] = $this->get_difficulty();

		return $arr;
	}