code: private static Schema wrapInTupleIfPig9(Schema schema) throws FrontendException {
        if (PigUtil.Pig9orNewer) {
            return new Schema(new FieldSchema("t",schema,DataType.TUPLE));
        } else {
            return schema;
        }
    }
docs: A helper function which wraps a Schema in a tuple (for Pig bags) if our version of pig makes it necessary