user: Question: What is the sum of crowd(s) at 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: ['Richmond', '16.9 (105)', 'St Kilda', '16.14 (110)', 'Punt Road Oval', 15000.0, '18 August 1956']
SQL:

assistant: SELECT SUM("Crowd") FROM "Table" WHERE "Venue" = 'Princes Park';