user: Question: Who is the opponent in week 15?
Columns: ['Week', 'Date', 'Opponent', 'Result', 'TV Time', 'Attendance']
Types: ['real', 'text', 'text', 'text', 'text', 'real']
Sample row: [2.0, 'September 23, 2001', 'Denver Broncos', 'L 38-17', 'ESPN 5:30pm', 50913.0]
SQL:

assistant: SELECT "Opponent" FROM "Table" WHERE "Week" = 15.0;