code: def plot_compare(self, other_plotter, legend=True):
          
          # TODO: add exception if the band structures are not compatible
          import matplotlib.lines as mlines
          plt = self.get_plot()
          data_orig = self.bs_plot_data()
          data = other_plotter.bs_plot_data()
          band_linewidth = 1
          for i in range(other_plotter._nb_bands):
              for d in range(len(data_orig['distances'])):
                  plt.plot(data_orig['distances'][d],
                           [e[str(Spin.up)][i] for e in data['energy']][d],
                           'c-', linewidth=band_linewidth)
                  if other_plotter._bs.is_spin_polarized:
                      plt.plot(data_orig['distances'][d],
                               [e[str(Spin.down)][i] for e in data['energy']][d],
                               'm--', linewidth=band_linewidth)
          if legend:
              handles = [mlines.Line2D([], [], linewidth=2,
                                       color='b', label='bs 1 up'),
                         mlines.Line2D([], [], linewidth=2,
                                       color='r', label='bs 1 down',
                                       linestyle="--"),
                         mlines.Line2D([], [], linewidth=2,
                                       color='c', label='bs 2 up'),
                         mlines.Line2D([], [], linewidth=2,
                                       color='m', linestyle="--",
                                       label='bs 2 down')]
  
              plt.legend(handles=handles)
          return plt
docs: plot two band structure for comparison. One is in red the other in blue
          (no difference in spins). The two band structures need to be defined
          on the same symmetry lines! and the distance between symmetry lines is
          the one of the band structure used to build the BSPlotter
  
          Args:
              another band structure object defined along the same symmetry lines
  
          Returns:
              a matplotlib object with both band structures