user: Question: What is the name of the winning driver where the circuit name is Posillipo?
Columns: ['Race Name', 'Circuit', 'Date', 'Winning driver', 'Constructor', 'Report']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['II Lombank Trophy', 'Snetterton', '26 March', 'Jack Brabham', 'Cooper - Climax', 'Report']
SQL:

assistant: SELECT "Winning driver" FROM "Table" WHERE "Circuit" = 'Posillipo';