pytho opencv 找到面積最大的連通域

if (cv2.__version__).split('.')[0] =='3':
    _, contours, _ = cv2.findContours(thresh, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_NONE)
else:
    contours, _ = cv2.findContours(thresh, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_NONE)

cnt = contours[np.argmax([cv2.contourArea(cnt) for cnt in contours])]