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_7 (opponent VARCHAR, game_site VARCHAR, record VARCHAR)
### Question:
Which Opponent has a Game site of heinz field, and a Record of 3–1?
### Answer:
SELECT opponent FROM table_name_7 WHERE game_site = "heinz field" AND record = "3–1"