CREATE OR REPLACE FUNCTION my_schema.my_function(param1 IN number) RETURN output1 IS
    cnumber NUMBER;
BEGIN
    cnumber := 2;
    RETURN (cnumber * param1);
EXCEPTION
    WHEN OTHERS THEN
        raise_application_error(-20001, 'An error was encountered - '
            || sqlcode || ' -ERROR- ' || sqlerrm);
END;