user: Question: What driver has more than 39 laps on gird 15?
Columns: ['Driver', 'Constructor', 'Laps', 'Time/Retired', 'Grid']
Types: ['text', 'text', 'real', 'text', 'real']
Sample row: ['Mika Häkkinen', 'McLaren - Mercedes', 53.0, '1:31:18.785', 2.0]
SQL:

assistant: SELECT "Driver" FROM "Table" WHERE "Laps" > 39.0 AND "Grid" = 15.0;