user: Question: What was the Attendance at the Game with a Result of W 21–7?
Columns: ['Week', 'Date', 'Opponent', 'Result', 'Record', 'Game Site', 'Attendance']
Types: ['real', 'text', 'text', 'text', 'text', 'text', 'real']
Sample row: [1.0, 'September 30, 1956', 'Chicago Bears', 'W 28–21', '1–0', 'Memorial Stadium', 45221.0]
SQL:

assistant: SELECT "Attendance" FROM "Table" WHERE "Result" = 'W 21–7';