How many drivers were in the Australian Grand Prix held in 2009?
SELECT count(*) FROM results AS T1 JOIN races AS T2 ON T1.raceid = T2.raceid WHERE T2.name = "Australian Grand Prix" AND YEAR = 2009
SELECT count(*) FROM results AS T1 JOIN races AS T2 ON T1.raceid = T2.raceid WHERE T2.name = "Australian Grand Prix" AND YEAR = 2009
[{'count(*)': 20}]