user: Question: At what arena was the September 21 game?
Columns: ['Date', 'Opponent', 'Score', 'Record', 'Arena']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['September 17', '@ Kings', '4–2', '0–1–0', 'Staples Center']
SQL:

assistant: SELECT "Arena" FROM "Table" WHERE "Date" = 'September 21';