code: def layer_height(self, layer_int):
          
          if layer_int == self.n_layers:
              if self.height is None:
                  return None
              return self.height - self.layer_depth(layer_int)
          else:
              return self.layer_depth(layer_int + 1) - self.layer_depth(layer_int)
docs: Get the layer height by layer id number.
  
          :param layer_int:
          :return: float, height of the soil layer