code: def make_plot(self):
          
  
          # sets levels of main contour plot
          colors1 = ['None', 'darkblue', 'blue', 'deepskyblue', 'aqua',
                     'greenyellow', 'orange', 'red', 'darkred']
  
          if len(self.contour_vals) > len(colors1) + 1:
              raise AttributeError("Reduce number of contours.")
  
          # produce filled contour of SNR
          sc = self.axis.contourf(self.xvals[0], self.yvals[0], self.zvals[0],
                                  levels=np.asarray(self.contour_vals), colors=colors1)
  
          self.colorbar.setup_colorbars(sc)
  
          # check for user desire to show separate contour line
          if self.snr_contour_value is not None:
              self.axis.contour(self.xvals[0], self.yvals[0], self.zvals[0],
                                np.array([self.snr_contour_value]),
                                colors='white', linewidths=1.5, linestyles='dashed')
  
          return
docs: This method creates the waterfall plot.