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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 ridgeplot(self, mult, linewidth, alpha, ax):
 """Draw ridgeplot for each plotter. Parameters mult : float How much to multiply height by. Set this to greater than 1 to have some overlap. linewidth : float Width of line on border of ridges alpha : float Transparency of ridges ax : Axes Axes to draw on """

        if alpha is None:
            alpha = 1.0
        zorder = 0
        for plotter in self.plotters.values():
            for x, y_min, y_max, color in plotter.ridgeplot(mult):
                if alpha == 0:
                    border = color
                else:
                    border = "k"
                ax.plot(x, y_max, "-", linewidth=linewidth, color=border, zorder=zorder)
                ax.plot(x, y_min, "-", linewidth=linewidth, color=border, zorder=zorder)
                ax.fill_between(x, y_min, y_max, alpha=alpha, color=color, zorder=zorder)
                zorder -= 1
        return ax