public function __construct() {

		add_filter( 'post_row_actions', array( $this, 'add_links' ), 1, 2 );

		add_filter( 'manage_lesson_posts_columns', array( $this, 'add_columns' ), 10, 1 );
		add_action( 'manage_lesson_posts_custom_column', array( $this, 'manage_columns' ), 10, 2 );

		add_action( 'restrict_manage_posts', array( $this, 'add_filters' ), 10, 2 );
		add_filter( 'parse_query', array( $this, 'parse_query_filters' ), 10, 1 );
	}