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 table_name_31 (class VARCHAR, race_title VARCHAR)
### Question:
What class of car had the XI Coppa Acerbo title?
### Answer:
SELECT class FROM table_name_31 WHERE race_title = "xi coppa acerbo"