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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 plot_vs(fignum, Xs, c, ls):
 """ plots vertical lines at Xs values Parameters _________ fignum : matplotlib figure number Xs : list of X values for lines c : color for lines ls : linestyle for lines """

    fig = plt.figure(num=fignum)
    for xv in Xs:
        bounds = plt.axis()
        plt.axvline(
            x=xv, ymin=bounds[2], ymax=bounds[3], linewidth=1, color=c, linestyle=ls)