function dozent_course_is_protected( $course = null ) {

		$is_protected = dozent_get_course_price_type( $course ) === 'protected';

		/**
		 * Filter the return value of dozent_course_is_protected(); function
		 *
		 * The course is free. Anyone can access its content by log-in into the site.
		 *
		 * @since DozentLMS 1.0.0
		 *
		 * @param  bool  $is_protected  Determine if the course is protected
		 * @param  int|object  $course  Post object
		 */

		return apply_filters( 'dozent_course_is_protected', $is_protected, $course );
	}