def draw_line(line): x1, y1, x2, y2 = line[0] cv2.line(img, (x1, y1), (x2, y2), (0, 0, 255), 2)这段代码出现错误，应该怎么改正

There seems to be a missing comma after `y1`. Here's the corrected code:

def draw_line(line):
    x1, y1, x2, y2 = line[0]
    cv2.line(img, (x1, y1), (x2, y2), (0, 0, 255), 2)