Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE singer (country VARCHAR, age INTEGER)
### Question:
Show countries where a singer above age 40 and a singer below 30 are from.
### Answer:
SELECT country FROM singer WHERE age > 40 INTERSECT SELECT country FROM singer WHERE age < 30