user: ### NOW ANSWER:
Question: In what time period were 578 built?
Columns: ['Model', 'Seats', 'Period', 'Built', 'Country']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Saab 90 Scandia', '24-32', '1946-1954', '18', 'Sweden']
SQL:

assistant: SELECT "Period" FROM "Table" WHERE "Built" = '578';