public static function assign_to_course( $course_id, $section_id, $lesson_id, $duplicate = true, $reset_order = true ) {

		llms_deprecated_function( __METHOD__, '5.7.0' );

		// Get position of next lesson.
		$section      = new LLMS_Section( $section_id );
		$lesson_order = $section->get_next_available_lesson_order();

		// First determine if lesson is associated with a course.
		// We need to know this because if it is already associated then we duplicate it and assign the dupe.
		$parent_course  = get_post_meta( $lesson_id, '_llms_parent_course', true );
		$parent_section = get_post_meta( $lesson_id, '_llms_parent_section', true );

		// Parent course exists, lets dupe this baby!.
		if ( $parent_course && true == $duplicate ) {
			$lesson_id = self::duplicate_lesson( $course_id, $section_id, $lesson_id );
		} else {
			// Add parent section and course to new lesson.
			update_post_meta( $lesson_id, '_llms_parent_section', $section_id );
			update_post_meta( $lesson_id, '_llms_parent_course', $course_id );

		}

		if ( $reset_order ) {
			update_post_meta( $lesson_id, '_llms_order', $lesson_order );
		}

		return $lesson_id;

	}