user: Question: What is the gdp of the country with an area of 83871 (km2)?
Columns: ['Member countries', 'Population', 'Area (km²)', 'GDP (billion US$)', 'GDP per capita (US$)']
Types: ['text', 'real', 'real', 'text', 'real']
Sample row: ['Austria', 8206524.0, 83871.0, '145.238', 18048.0]
SQL:

assistant: SELECT "GDP (billion US$)" FROM "Table" WHERE "Area (km²)" = 83871.0;