docs: def plot_connectivity_surrogate(self, measure_name, repeats=100, fig=None):
          """ Plot spectral connectivity measure under the assumption of no actual connectivity.
  
          Repeatedly samples connectivity from phase-randomized data. This provides estimates of the connectivity
          distribution if there was no causal structure in the data.
  
          Parameters
          ----------
          measure_name : str
              Name of the connectivity measure to calculate. See :class:`Connectivity` for supported measures.
          repeats : int, optional
              How many surrogate samples to take.
          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.
          """
          cb = self.get_surrogate_connectivity(measure_name, repeats)
  
          self._prepare_plots(True, False)
  
          cu = np.percentile(cb, 95, axis=0)
  
          fig = self.plotting.plot_connectivity_spectrum([cu], self.fs_, freq_range=self.plot_f_range, fig=fig)
  
          return fig