user: Question: Which Venue has a Notes of Heptathlon, and a Year of 1991?
Columns: ['Year', 'Competition', 'Venue', 'Position', 'Notes']
Types: ['real', 'text', 'text', 'text', 'text']
Sample row: [1991.0, 'Pan American Games', 'Havana, Cuba', '1st', 'Heptathlon']
SQL:

assistant: SELECT "Venue" FROM "Table" WHERE "Notes" = 'Heptathlon' AND "Year" = 1991.0;