concentric colored circles

whats up guys .. i just have a Question.. i am working on a concetric circles or u can say a circle andd surrounded by 4 rings .. i wanna make them all color by clicking on them .. when i click on one of the rings or the circle .. it changes its color randomly .. i am done with drawing the circles and i came up with a mathimatical formula for my work .. r=math.sqrt(((g etX-200)**2+((getY-200)**2)
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