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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 add_coord(self, x, y):
 """ Adds a coord to the polyline and creates another circle """

        x = x*self.x_factor
        y = y*self.y_factor
        self.plotData.add_coord(x, y)
        self.circles_list.append(gui.SvgCircle(x, y, self.circle_radius))
        self.append(self.circles_list[-1])
        if len(self.circles_list) > self.maxlen:
            self.remove_child(self.circles_list[0])
            del self.circles_list[0]