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 employees (department_id VARCHAR, manager_id VARCHAR, employee_id VARCHAR)
### Question:
Find the ids of the departments where any manager is managing 4 or more employees.
### Answer:
SELECT DISTINCT department_id FROM employees GROUP BY department_id, manager_id HAVING COUNT(employee_id) >= 4