user: Question: When was the game that was held at the Princes Park?
Columns: ['Home team', 'Home team score', 'Away team', 'Away team score', 'Venue', 'Crowd', 'Date']
Types: ['text', 'text', 'text', 'text', 'text', 'real', 'text']
Sample row: ['Footscray', '7.8 (50)', 'Richmond', '11.15 (81)', 'Western Oval', 15500.0, '6 August 1927']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Venue" = 'Princes Park';