user: Question: Which Wins have a Class of 500cc, and a Year smaller than 1975?
Columns: ['Year', 'Class', 'Team', 'Points', 'Rank', 'Wins']
Types: ['real', 'text', 'text', 'real', 'text', 'real']
Sample row: [1973.0, '250cc', 'Yamaha', 21.0, '11th', 0.0]
SQL:

assistant: SELECT "Wins" FROM "Table" WHERE "Class" = '500cc' AND "Year" < 1975.0;