user: Question: Who did the Patriots play in week 4?
Columns: ['Week', 'Date', 'Opponent', 'Result', 'Attendance']
Types: ['real', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'September 1, 1991', 'at Indianapolis Colts', 'W 16–7', '49,961']
SQL:

assistant: SELECT "Opponent" FROM "Table" WHERE "Week" = 4.0;