what's the date with attendance being 40657
{'header': ['Week', 'Date', 'Opponent', 'Result', 'Record', 'Game Site', 'Attendance'], 'page_title': '1975 Baltimore Colts season', 'section_title': 'Schedule', 'caption': 'Schedule', 'rows': [['1', 'September 21, 1975', 'at Chicago Bears', 'W 35–7', '1–0', 'Soldier Field', '54152'], ['2', 'September 28, 1975', 'Oakland Raiders', 'L 20–31', '1–1', 'Memorial Stadium', '40657'], ['3', 'October 5, 1975', 'at Los Angeles Rams', 'L 13–24', '1–2', 'Los Angeles Memorial Coliseum', '62491'], ['4', 'October 12, 1975', 'Buffalo Bills', 'L 31–38', '1–3', 'Memorial Stadium', '43907'], ['5', 'October 19, 1975', 'at New England Patriots', 'L 10–21', '1–4', 'Schaeffer Stadium', '51417'], ['6', 'October 26, 1975', 'at New York Jets', 'W 45–28', '2–4', 'Shea Stadium', '55137'], ['7', 'November 2, 1975', 'Cleveland Browns', 'W 21–7', '3–4', 'Memorial Stadium', '35235'], ['8', 'November 9, 1975', 'at Buffalo Bills', 'W 42–35', '4–4', 'Rich Stadium', '77320'], ['9', 'November 16, 1975', 'New York Jets', 'W 52–19', '5–4', 'Memorial Stadium', '52097'], ['10', 'November 23, 1975', 'at Miami Dolphins', 'W 33–17', '6–4', 'Miami Orange Bowl', '61986'], ['11', 'November 30, 1975', 'Kansas City Chiefs', 'W 28–14', '7–4', 'Memorial Stadium', '42122'], ['12', 'December 7, 1975', 'at New York Giants', 'W 21–0', '8–4', 'Shea Stadium', '49863'], ['13', 'December 14, 1975', 'Miami Dolphins', 'W 10–7', '9–4', 'Memorial Stadium', '59398']]}