user: ### NOW ANSWER:
Question: what is the nationality when the heat is less than 3 and the time is 2:35.31?
Columns: ['Rank', 'Heat', 'Name', 'Nationality', 'Time']
Types: ['real', 'real', 'text', 'text', 'text']
Sample row: [1.0, 3.0, 'Svetlana Varganova Category:Articles with hCards', 'Soviet Union', '2:29.77']
SQL:

assistant: SELECT "Nationality" FROM "Table" WHERE "Heat" < 3.0 AND "Time" = '2:35.31';