user: Question: Which driver won the Indianapolis 500 the year the Chaparral team also won it?
Columns: ['Name', 'Pole Position', 'Fastest Lap', 'Winning driver', 'Winning team', 'Report']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Datsun Twin 200', 'Johnny Rutherford', 'Unknown', 'Johnny Rutherford', 'Chaparral', 'Report']
SQL:

assistant: SELECT "Winning driver" FROM "Table" WHERE "Winning team" = 'Chaparral' AND "Name" = 'Indianapolis 500';