user: Question: What country has Grandstand Stadium as the stadium?
Columns: ['Rank', 'Stadium', 'Capacity', 'City', 'Country', 'Tournament hosted']
Types: ['text', 'text', 'real', 'text', 'text', 'text']
Sample row: ['1', 'Arthur Ashe Stadium', 23200.0, 'New York City', 'United States', 'US Open']
SQL:

assistant: SELECT "Country" FROM "Table" WHERE "Stadium" = 'Grandstand Stadium';