user: Question: what builder is now Retired
Columns: ['Name', 'Pennant number', 'Builder', 'Laid Down', 'Launched', 'Commissioned', 'Current status']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Minerva', 'F 551', 'Fincantieri , Riva Trigoso', '11 March 1985', '3 April 1986', '10 June 1987', 'Retired']
SQL:

assistant: SELECT "Pennant number" FROM "Table" WHERE "Current status" = 'Retired';