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_12707313_2 (constr VARCHAR, first_win VARCHAR)
### Question:
Name the number of constr with the first win at the 1978 brazilian grand prix
### Answer:
SELECT COUNT(constr) FROM table_12707313_2 WHERE first_win = "1978 Brazilian Grand Prix"