One of the most essential concepts of pygame to start making a game you will need to understand is loading images and blitting them to the screen.
blit stands for block image transfer, to me it feels a lot like layering up layers/images in photoshop or Gimp.
I started by making a spotlight in Gimp, by opening a 64x64 pixel image and painting the center with a very soft brush.
This is what it looks like
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