text: from topomc.common.coordinates import Coordinates
  from topomc.processes.topomap import Depression, Hill, TopoMap
  from topomc.symbol import PointSymbol
  
  
  class Knoll(PointSymbol):
      def __init__(self, processes):
          self.topomap = super().__init__(processes, klass=TopoMap)
  
          self.set_properties(color="#BA5E1A", pointsize=0.7)
  
      def render(self):
          for isoline in self.topomap.closed_isolines:
              if isoline.small_feature and isinstance(isoline, Hill):
                  if isoline.first_small_feature:
                      if isoline.depth < 3:
                          self.plot(
                              Coordinates(
                                  sum([p.x for p in isoline.vertices])
                                  / len(isoline.vertices)
                                  + 0.5,
                                  sum([p.y for p in isoline.vertices])
                                  / len(isoline.vertices)
                                  + 0.5,
                              )
                          )
  