user: Question: How many rounds did Ken Wharton go?
Columns: ['Entrant', 'Constructor', 'Chassis', 'Engine', 'Tyre', 'Driver', 'Rounds']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Officine Alfieri Maserati', 'Maserati', 'A6GCM', 'Maserati A6 2.0 L6', 'P', 'Juan Manuel Fangio', '1, 3–9']
SQL:

assistant: SELECT "Rounds" FROM "Table" WHERE "Driver" = 'Ken Wharton';