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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_mate_center(self, angle=0):
 """ Mate at ring's center rotated ``angle`` degrees. :param angle: rotation around z-axis (unit: deg) :type angle: :class:`float` :return: mate in ring's center rotated about z-axis :rtype: :class:`Mate <cqparts.constraint.Mate>` """

        return Mate(self, CoordSystem.from_plane(
            cadquery.Plane(
                origin=(0, 0, self.width / 2),
                xDir=(1, 0, 0),
                normal=(0, 0, 1),
            ).rotated((0, 0, angle))  # rotate about z-axis
        ))