user: Question: Which Date has a Game site of Shea Stadium, and a Week of 5?
Columns: ['Week', 'Date', 'Opponent', 'Result', 'Game site', 'Attendance']
Types: ['real', 'text', 'text', 'text', 'text', 'real']
Sample row: [1.0, '1975-09-21', 'at Buffalo Bills', 'L 42–14', 'Rich Stadium', 77837.0]
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Game site" = 'Shea Stadium' AND "Week" = 5.0;