user: Question: What was round of 64 of the Singles event when the result of round 16 was Did not advance and the athlete was Iveta Benešová?
Columns: ['Athlete', 'Event', 'Round of 64', 'Round of 32', 'Round of 16', 'Quarterfinals']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Iveta Benešová', 'Singles', 'Mirza ( IND ) W 6–2, 2–1 r', 'V Williams ( USA ) L 1–6, 4–6', 'Did not advance', 'Did not advance']
SQL:

assistant: SELECT "Round of 64" FROM "Table" WHERE "Event" = 'Singles' AND "Round of 16" = 'Did not advance' AND "Athlete" = 'Iveta Benešová';