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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 get_scan_plot(self, coords=None):
 """ Get a matplotlib plot of the potential energy surface. Args: coords: internal coordinate name to use as abcissa. """

        from pymatgen.util.plotting import pretty_plot

        plt = pretty_plot(12, 8)

        d = self.read_scan()

        if coords and coords in d["coords"]:
            x = d["coords"][coords]
            plt.xlabel(coords)
        else:
            x = range(len(d["energies"]))
            plt.xlabel("points")

        plt.ylabel("Energy (eV)")

        e_min = min(d["energies"])
        y = [(e - e_min) * Ha_to_eV for e in d["energies"]]

        plt.plot(x, y, "ro--")
        return plt