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Hand with Reflecting Sphere - M.C. Escher (1935)
(4.bp.blogspot.com)
Wander the gallery. Look at the art. Be polite. If you feel able please post some great art :)
You can see all around the ball is nothing. No door.
The subject is the ball. What is behind the ball was left out.
From the reflection you can actually recreate what is behind the ball using this website.
That may work in real life, but this is a hand drawn image.
The levels of distortion around the edges of Eschers drawing don't match what is shown in your example.