user: Question: Which theme has a Episode of Top 6?
Columns: ['Episode', 'Theme', 'Song choice', 'Original artist', 'Order #', 'Result']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Audition', "Auditioner's Choice", '"Sería fácil"', 'Luis Fonsi', 'N/A', 'Advanced']
SQL:

assistant: SELECT "Theme" FROM "Table" WHERE "Episode" = 'Top 6';