oracle pipelined function return rowtype

1-- Return types
2CREATE TYPE t_tf_row AS OBJECT (
3  	id           NUMBER,
4  	description  VARCHAR2(50)
5);
6CREATE TYPE t_tf_tab IS TABLE OF t_tf_row;
7-- Build a pipelined table function.
8CREATE OR REPLACE FUNCTION get_tab_ptf (p_rows IN NUMBER) 
9	RETURN t_tf_tab PIPELINED AS
10BEGIN
11  	FOR i IN 1 .. p_rows LOOP
12    	PIPE ROW(t_tf_row(i, 'Description for ' || i));   
13  	END LOOP;
14  	RETURN;
15END;
16-- Test it.
17SELECT * FROM TABLE(get_tab_ptf(10)) ORDER BY id DESC;