user: Question: What's the rounds for Jenson Button with a BMW E41 engine?
Columns: ['Entrant', 'Constructor', 'Chassis', 'Engine †', 'Tyre', 'Driver', 'Rounds']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['West McLaren Mercedes', 'McLaren - Mercedes', 'MP4/15', 'Mercedes FO110J', 'B', 'Mika Häkkinen', 'All']
SQL:

assistant: SELECT "Rounds" FROM "Table" WHERE "Engine †" = 'BMW E41' AND "Driver" = 'Jenson Button';