user: Question: What was the stage when the winner was Luis León Sánchez?
Columns: ['Stage', 'Winner', 'General Classification', 'Mountains Classification', 'Sprint Classification', 'Young Rider Classification', 'Team Classification', 'Aggressive Rider']
Types: ['real', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'André Greipel', 'André Greipel', 'Timothy Roe', 'Martin Kohler', 'Martin Kohler', 'Ag2r-La Mondiale', 'Timothy Roe']
SQL:

assistant: SELECT "Stage" FROM "Table" WHERE "Winner" = 'Luis León Sánchez';