Oracle Message ORA-24230 - input to DBMS_DDL.WRAP is not a legal PL/SQL unit

ERRORinput to DBMS_DDL.WRAP is not a legal PL/SQL unit
CAUSEThe input supplied to DBMS_DDL.WRAP or DBMS_DDL.CREATE_WRAPPED did not specify a legal PL/SQL package specification, package body, type specification, type body, function or procedure. This error can occur if you used incorrect syntax in the CREATE OR REPLACE statement or specified a unit that cannot be wrapped (e.g., a trigger or anonymous block).
ACTIONProvide a legal PL/SQL unit as input.