user: Question: What's the total number built with a chassis code of w108.057?
Columns: ['Model', 'Chassis code', 'Production time', 'Number built', 'Engine']
Types: ['text', 'text', 'text', 'real', 'text']
Sample row: ['250S', 'W108.012', '07/65 - 03/69', 74.677, '2.5L M108 I6']
SQL:

assistant: SELECT SUM("Number built") FROM "Table" WHERE "Chassis code" = 'w108.057';