user: Question: What is the Quantity of the engine Model PG-2901?
Columns: ['Model', 'Built', 'Quantity', 'Seats', 'Length', 'Engine']
Types: ['text', 'text', 'real', 'real', 'text', 'text']
Sample row: ['PG-2501', '1939–1940', 8.0, 25.0, 'ft1in (m)', 'GMC 248 6 cyl. gas']
SQL:

assistant: SELECT "Quantity" FROM "Table" WHERE "Model" = 'PG-2901';