code: def add_tlink(self,my_tlink):
          
          if self.temporalRelations_layer is None:
              self.temporalRelations_layer = CtemporalRelations()
              self.root.append(self.temporalRelations_layer.get_node())
          self.temporalRelations_layer.add_tlink(my_tlink)
docs: Adds a tlink to the temporalRelations layer
          @type my_tlink: L{Ctlink}
          @param my_tlink: tlink object