If the date is 7-21-2006, who was the opponent?
CREATE TABLE table_25957 (
    "Edition" text,
    "Round" text,
    "Date" text,
    "Against" text,
    "Surface" text,
    "Opponent" text,
    "Result" text,
    "Outcome" text
)
SELECT "Opponent" FROM table_25957 WHERE "Date" = '7-21-2006'
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: If the date is 7-21-2006, who was the opponent? ### Input: CREATE TABLE table_25957 (
    "Edition" text,
    "Round" text,
    "Date" text,
    "Against" text,
    "Surface" text,
    "Opponent" text,
    "Result" text,
    "Outcome" text
) ### Response: SELECT "Opponent" FROM table_25957 WHERE "Date" = '7-21-2006'