user: Question: What winner has Pierre Rolland as mountains classification, with 7 as the stage?
Columns: ['Stage', 'Winner', 'General classification', 'Mountains classification', 'Points classification', 'Team Classification']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['P', 'Levi Leipheimer', 'Levi Leipheimer', 'no award', 'Levi Leipheimer', 'Astana']
SQL:

assistant: SELECT "Winner" FROM "Table" WHERE "Mountains classification" = 'Pierre Rolland' AND "Stage" = '7';