docs: def plot_connectivity_topos(self, fig=None):
          """ Plot scalp projections of the sources.
  
          This function only plots the topos. Use in combination with connectivity plotting.
  
          Parameters
          ----------
          fig : {None, Figure object}, optional
              Where to plot the topos. f set to **None**, a new figure is created. Otherwise plot into the provided
              figure object.
  
          Returns
          -------
          fig : Figure object
              Instance of the figure in which was plotted.
          """
          self._prepare_plots(True, False)
          if self.plot_outside_topo:
              fig = self.plotting.plot_connectivity_topos('outside', self.topo_, self.mixmaps_, fig)
          elif self.plot_diagonal == 'topo':
              fig = self.plotting.plot_connectivity_topos('diagonal', self.topo_, self.mixmaps_, fig)
          return fig