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 airports (dst_apid VARCHAR, src_apid VARCHAR, apid VARCHAR, country VARCHAR); CREATE TABLE routes (dst_apid VARCHAR, src_apid VARCHAR, apid VARCHAR, country VARCHAR)
### Question:
Find the number of routes from the United States to Canada.
### Answer:
SELECT COUNT(*) FROM routes WHERE dst_apid IN (SELECT apid FROM airports WHERE country = 'Canada') AND src_apid IN (SELECT apid FROM airports WHERE country = 'United States')