user: Question: For which jockey was the weight in kg 53.5? 
Columns: ['Saddle cloth', 'Horse', 'Trainer', 'Jockey', 'Weight (kg)', 'Barrier [b ]', 'Placing']
Types: ['real', 'text', 'text', 'text', 'text', 'real', 'text']
Sample row: [1.0, 'Viewed', 'Bart Cummings', 'Brad Rawiller', '58.0', 9.0, '7']
SQL:

assistant: SELECT "Jockey" FROM "Table" WHERE "Weight (kg)" = '53.5';