Python displaying images with url and arrow-Keys

I have written a Python console application which searches reddit for images. They should be then displayed. With arrow-keys the user should be able to go to the next or previous image. Moreover, I want to resize every image so it fits into a 800×800 frame.

I have already triend tkinter and opencv. Using tkinter I wasnt able to resize the images (dont know why) and using opencv worked.

So, the Input is an array of image-urls. Can someone recommend a library to me or share some code how to do that? Espacially the thing with the error-keys would be nice.