Creating password in oracle

/*Use the function to create password with user name*/

CREATE OR REPLACE function f_Password(p_username in varchar2, p_password in varchar2)
return varchar2
is
begin
  return dbms_obfuscation_toolkit.md5
     (input =>
         utl_raw.cast_to_raw(upper(p_username)||'/'||p_password)
     );
end f_Password;
/