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 PersonFriend (friend VARCHAR, name VARCHAR, YEAR INTEGER)
### Question:
Who is the friend of Zach with longest year relationship?
### Answer:
SELECT friend FROM PersonFriend WHERE name = 'Zach' AND YEAR = (SELECT MAX(YEAR) FROM PersonFriend WHERE name = 'Zach')