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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_cable_length(stats, plotpath):
 """ Cable length per MV grid district """


    # cable and line kilometer distribution
    f, axarr = plt.subplots(2, 2, sharex=True)
    stats.hist(column=['Length of MV overhead lines'], bins=5, alpha=0.5, ax=axarr[0, 0])
    stats.hist(column=['Length of MV underground cables'], bins=5, alpha=0.5, ax=axarr[0, 1])
    stats.hist(column=['Length of LV overhead lines'], bins=5, alpha=0.5, ax=axarr[1, 0])
    stats.hist(column=['Length of LV underground cables'], bins=5, alpha=0.5, ax=axarr[1, 1])

    plt.savefig(os.path.join(plotpath,
                             'Histogram_cable_line_length.pdf'))