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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_seebeck_mu(self, temp=600, output='eig', xlim=None):
 """ Plot the seebeck coefficient in function of Fermi level Args: temp: the temperature xlim: a list of min and max fermi energy by default (0, and band gap) Returns: a matplotlib object """

        import matplotlib.pyplot as plt
        plt.figure(figsize=(9, 7))
        seebeck = self._bz.get_seebeck(output=output, doping_levels=False)[
            temp]
        plt.plot(self._bz.mu_steps, seebeck,
                 linewidth=3.0)

        self._plot_bg_limits()
        self._plot_doping(temp)
        if output == 'eig':
            plt.legend(['S$_1$', 'S$_2$', 'S$_3$'])
        if xlim is None:
            plt.xlim(-0.5, self._bz.gap + 0.5)
        else:
            plt.xlim(xlim[0], xlim[1])
        plt.ylabel("Seebeck \n coefficient  ($\\mu$V/K)", fontsize=30.0)
        plt.xlabel("E-E$_f$ (eV)", fontsize=30)
        plt.xticks(fontsize=25)
        plt.yticks(fontsize=25)
        plt.tight_layout()
        return plt