user: Question: What is the surface of the tournament with Cédric Pioline as the opponent in the final?
Columns: ['Date', 'Tournament', 'Surface', 'Opponent in the final', 'Score']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['13 October 1986', 'Toulouse , France', 'Hard (i)', 'Jan Gunnarsson', '4–6, 6–3, 6–2']
SQL:

assistant: SELECT "Surface" FROM "Table" WHERE "Opponent in the final" = 'Cédric Pioline';