How to copy file to and from ASM?

create or replace directory SOURCE_DIR as '+DSKGRP1/ORA10G/ORADATA';

create or replace directory ORACLE_DEST as '/oracle/ORA10G/ORADATA';

BEGIN
dbms_file_transfer.copy_file(source_directory_object =>
'SOURCE_DIR', source_file_name => 'system.721.728614431',
destination_directory_object => 'ORACLE_DEST',
destination_file_name => 'system.dbf');
END;
/