user: Question: Which polling firm put T. Papadopoulos at 31%?
Columns: ['Polling Firm', 'Date Published', 'T. Papadopoulos', 'D. Christofias', 'I. Kasoulidis', 'K. Themistokleous']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Symmetron', '3 October 2007', '32.9%', '27.5%', '27.6%', '0.4%']
SQL:

assistant: SELECT "Polling Firm" FROM "Table" WHERE "T. Papadopoulos" = '31%';