code: def _colorbar_ticks(minval, maxval):
      
      if not (np.isfinite(minval) and np.isfinite(maxval)):
          return [0, 0, 0]
      elif minval == maxval:
          return [minval]
      else:
          # Add eps to ensure values stay inside the range of the colorbar.
          # Otherwise they may occationally not display.
          eps = (maxval - minval) / 1e5
          return [minval + eps, (maxval + minval) / 2., maxval - eps]
docs: Return the ticks (values show) in the colorbar.