user: Question: Who won the gold when Bertil Ahlin Sweden won the silver?
Columns: ['Event', 'Gold', 'Silver', 'Bronze', '4th place']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Flyweight (– 51 kilograms)', 'Luis Martinez Zapata Spain', 'James Clinton Scotland', 'Frantisek Majdloch Czechoslovakia', 'I. Bendai Hungary']
SQL:

assistant: SELECT "Gold" FROM "Table" WHERE "Silver" = 'Bertil Ahlin Sweden';