How many people attended when Wake Forest played Virginia Tech?
CREATE TABLE table_name_21 (
    attendance INTEGER,
    opponent VARCHAR
)
SELECT SUM(attendance) FROM table_name_21 WHERE opponent = "virginia tech"
Below are sql tables schemas paired with instruction that describes a task. Using valid SQLite, write a response that appropriately completes the request for the provided tables. ### Instruction: How many people attended when Wake Forest played Virginia Tech? ### Input: CREATE TABLE table_name_21 (
    attendance INTEGER,
    opponent VARCHAR
) ### Response: SELECT SUM(attendance) FROM table_name_21 WHERE opponent = "virginia tech"