In Oracle SQL Developer, how do I create or update a procedure and have the schema name be a variable:

define my_schema_name = 'schema_1';  

    CREATE OR REPLACE PROCEDURE my_schema_name.updateDBUSER(
         p_userid IN DBUSER.USER_ID%TYPE,
         p_username IN DBUSER.USERNAME%TYPE)
    IS
    BEGIN

      UPDATE DBUSER SET USERNAME = p_username where USER_ID = p_userid;

      COMMIT;

    END;

define my_schema_name = 'SCHEMA_1';

CREATE OR REPLACE PROCEDURE "&my_schema_name".updateDBUSER(
     p_userid IN DBUSER.USER_ID%TYPE,
     p_username IN DBUSER.USERNAME%TYPE)
IS
BEGIN

  UPDATE DBUSER SET USERNAME = p_username where USER_ID = p_userid;

  COMMIT;

END;