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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(self, ax=None, **kwargs):
 """ Plot the histogram with matplotlib, returns `matplotlib` figure. """

        ax, fig, plt = get_ax_fig_plt(ax)

        yy = [len(v) for v in self.values]
        ax.plot(self.binvals, yy, **kwargs)

        return fig