user: Question: Who had the fastest lap when the winning driver is Giorgio Sanna?
Columns: ['Round', 'Circuit', 'Series', 'Pole Position', 'Fastest Lap', 'Winning Driver', 'Winning Team']
Types: ['real', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'Vallelunga', 'Italian', 'Gianni Morbidelli', 'Gianni Morbidelli', 'Gianni Morbidelli', 'Audi Sport Italia']
SQL:

assistant: SELECT "Fastest Lap" FROM "Table" WHERE "Winning Driver" = 'Giorgio Sanna';