This function draws a filled circle in an image at the provided coordinates with specified radius and color.
ImageNum : The number of the image. You can use a number from 0 to 63 (included).
x,y : Coordinates of the center of the circle.
Radius : Radius of the circle to draw.
Color : The color used for drawing the polygon.
A boolean value. True if the operation succeeded. False is returned if the image doesn't exists or if the image number is out of bound.
To do.
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To do