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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 rotate(self, angle, x=0, y=0):
 """Rotate element by given angle around given pivot. Parameters angle : float rotation angle in degrees x, y : float pivot coordinates in user coordinate system (defaults to top-left corner of the figure) """

        self.root.set("transform", "%s rotate(%f %f %f)" %
                      (self.root.get("transform") or '', angle, x, y))