drawEllipse draws a circle that is not a circle

When you draw a circle with QPainter.drawEllipse it has not the same radius in all perimeters points. You must zoom in deep to see it.

For example radius is correct for 0 and for 90 degrees but not for 45 degrees.

Draw a circle. Draw a line from center of the circle with length of radius under 45 degrees. Then zoom end of the line and perimeter of the circle.