Open a new document with transparent background. Create a new layer and hit D on the keyboard. Grab Rectangular Marquee Tool and make a rectangle. Fill it with the foregroundcolour (black).
Create a new layer and grab Elliptical Marquee Tool. Hold down Shift while you make the selection of the cirkel. Fill it with a grey colour. Grab Move Tool and place the cirkel in one of the rectangles cornors.
Go to Select > Inverse (ctrl + shift + i) and then grab Brush Tool. Set Brush to 35 px and Mode to Clear. Activate the rectangle-layer and do slowly remove the corner of the rectangle.
Remove the selection (ctrl + d). Do the same with the other cornors.
You are finish.
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