protected function post_types() {

		$type  = $this->get( 'type' );
		$types = array();
		if ( 'any' === $type ) {
			$types = $this->allowed_post_types;
		} elseif ( 'achievement' === $type ) {
			$types = array( 'llms_my_achievement' );
		} elseif ( 'certificate' === $type ) {
			$types = array( 'llms_my_certificate' );
		}

		return $types;

	}