How to use wrap utility to encode Oracle database source code Object

The wrap program provided by Oracle encodes the PL/SQL source code but does not encrypt it.

select owner||'.'||name from dba_source
where
line=1
and
owner not in ('SYS', 'CTXSYS', 'MDSYS', 'ODM', 'OE', 'OLAPSYS',
'ORDPLUGINS', 'ORDSYS', 'OUTLN', 'PM', 'QS_ADM',
'RMAN', 'SYSTEM', 'WKSYS','WMSYS','XDB')
and
owner not like 'OEM%'
and
text not like '%wrapped%'
and
type in ('PACKAGE BODY','FUNCTION','PROCEDURE');