function dozent_curriculum_content( $single_curriculum = null, $echo = true ) {
		global $post;

		$post = get_post( $single_curriculum );
		$course_id = dozent_get_course_id_by_content( $post );

		/**
		 * Filter default curriculum lock status, single curriculum pre content.
		 *
		 * If this filter return something that's not false, null, or empty, then the return value will be print in the curriculum content area.
		 * This filter useful for make integration that required to lock curriculum content based on condition.
		 * Default usage to check if proper access permission has based on the course price time.
		 *
		 * @since DozentLMS 1.0.0
		 *
		 * @param  bool false False Return
		 * @param  object  $post  Curriculum / course content Object
		 * @param  int  $course_id  Course ID
		 */

		$output = apply_filters( 'dozent_is_curriculum_locked', false, $post, $course_id );

		if ( ! $output ) {
			ob_start();

			setup_postdata( $post );

			$post_type = $post->post_type;
			$tmpl_dir = str_replace( 'dozent_', '', $post_type );

			/**
			 * Filter Curriculum item content template path
             *
             * Curriculum content could be lecture,quiz,assignment
             *
             * @since DozentLMS 1.0.0
             *
             * @param string $path Content Template Path
             * @param string $post_type Current Post Type
             * @param object $post_type Current Post Object
			 */

			$template = apply_filters( 'dozent_curriculum_content_template', "single/{$tmpl_dir}/content", $post_type, $post );

			dozent_load_template( $template, compact( 'post' ) );
			wp_reset_postdata();

			$output = apply_filters( "single/{$post_type}/content", ob_get_clean(), $post );
		}

		if ( $echo ) {
			echo $output;
		}

		return $output;
	}