opencv-python namedWindow() can't resize window - opencv

I am using namedWindow() function in my code to resize the image's window. The mouse cursor showing i can resize the windows, but it actually can't. Here is my code
import numpy as np
import cv2
img=cv2.imread('/home/jeff/Downloads/iphone.png', 1)
cv2.namedWindow('image',cv2.WINDOW_NORMAL)
cv2.imshow('image',img)
cv2.waitKey(0)
cv2.destroyAllWindows()
Please assist. Thanks.

Replace code line cv2.namedWindow('image',cv2.WINDOW_NORMAL) with following:
cv2.namedWindow('image',cv2.WINDOW_AUTOSIZE)

There is a bug (at least in v3.2.0) that the resizing does not work if the image is bigger than the screen resolution. See the issue on GitHub.

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