user: Question: What date was the Tigullio Circuit?
Columns: ['Name', 'Circuit', 'Date', 'Winning driver', 'Winning constructor', 'Report']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Tigullio Circuit', 'Tigullio', '13 April', 'Tazio Nuvolari', 'Bianchi', 'Report']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Circuit" = 'Tigullio';