to get th coordinates of sift keypoints

edit

this is my code to detect and display keypoints (im using opencv 3.1.0 and python 2.7 )

import cv2
import numpy as np

img = cv2.imread('info-tabs3.jpg')
gray= cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)

sift = cv2.xfeatures2d.SIFT_create()
kp = sift.detect(gray,None)
pts = np.float([kp[idx].pt for idx in len(kp)]).reshape(-1, 1, 2)
print 'The list of detected keypoints is:' pts.pt

img=cv2.drawKeypoints(gray,kp,img)

cv2.imwrite('sift_keypoints.jpg',img)
cv2.imshow('window',img)
cv2.waitKey(10000)
cv2.destroyAllWindows()

the erreor displayed is :

File "sift.py", line 10
    print 'The list of detected keypoints is:' pts.pt
    ^
SyntaxError: invalid syntax

as you can see im getting a syntax error, any corrections in the code then please do tell .