Using MULTISET EXCEPT with PLSQL Nested Tables

DECLARE 
 
TYPE names IS TABLE OF VARCHAR2(20); 
 
family names := names('Mercy','Prabu','Ryan','Reza'); 
children names := names('Ryan','Reza'); 
parents names; 
 
BEGIN 
 
parents := family MULTISET EXCEPT children; 
 
DBMS_OUTPUT.put_line('The parents are: '); 
FOR idx IN 1..parents.COUNT  
LOOP 
    DBMS_OUTPUT.put_line(parents(idx)); 
END LOOP; 
 
END;