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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 histogram(series, **kwargs):
 """Plot an histogram of the data. Parameters series: Series The data to plot. Returns ------- str The resulting image encoded as a string. """

    imgdata = BytesIO()
    plot = _plot_histogram(series, **kwargs)
    plot.figure.subplots_adjust(left=0.15, right=0.95, top=0.9, bottom=0.1, wspace=0, hspace=0)
    plot.figure.savefig(imgdata)
    imgdata.seek(0)
    result_string = 'data:image/png;base64,' + quote(base64.b64encode(imgdata.getvalue()))
    # TODO Think about writing this to disk instead of caching them in strings
    plt.close(plot.figure)
    return result_string