docs: def _apply_new_data_port_default_value(self, path, new_default_value_str):
          """Applies the new default value of the data port defined by path
  
          :param str path: The path identifying the edited variable
          :param str new_default_value_str: New default value as string
          """
          try:
              data_port_id = self.list_store[path][self.ID_STORAGE_ID]
              if isinstance(self.model.state, LibraryState):
                  # this always has to be true, as the runtime value column can only be edited
                  # if the use_runtime_value flag is True
                  if self.list_store[path][self.USE_RUNTIME_VALUE_STORAGE_ID]:
                      self.set_data_port_runtime_value(data_port_id, new_default_value_str)
              else:
                  if str(self.state_data_port_dict[data_port_id].default_value) != new_default_value_str:
                      self.state_data_port_dict[data_port_id].default_value = new_default_value_str
          except (TypeError, AttributeError) as e:
              logger.exception("Error while changing default value")