user: Question: How many laps are associated with a time of + 1:39.591?
Columns: ['Driver', 'Constructor', 'Laps', 'Time/Retired', 'Grid']
Types: ['text', 'text', 'real', 'text', 'real']
Sample row: ['Nelson Piquet', 'Williams - Honda', 44.0, '1:21:25.091', 4.0]
SQL:

assistant: SELECT "Laps" FROM "Table" WHERE "Time/Retired" = '+ 1:39.591';