user: Question: Which Points against has a Lost of 13, and Points for of 671?
Columns: ['Club', 'Played', 'Drawn', 'Lost', 'Points for', 'Points against', 'Points difference', 'Points']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Club', 'Played', 'Drawn', 'Lost', 'Points for', 'Points against', 'Points difference', 'Points']
SQL:

assistant: SELECT "Points against" FROM "Table" WHERE "Lost" = '13' AND "Points for" = '671';