docs: def _generate_element_meta_data(self, meta_data):
          """Generate meta data for state elements and add it to the given dictionary
  
          This method retrieves the meta data of the state elements (data ports, outcomes, etc) and adds it to the
          given meta data dictionary.
  
          :param meta_data: Dictionary of meta data
          """
          for data_port_m in self.input_data_ports:
              self._copy_element_meta_data_to_meta_file_data(meta_data, data_port_m, "input_data_port",
                                                             data_port_m.data_port.data_port_id)
          for data_port_m in self.output_data_ports:
              self._copy_element_meta_data_to_meta_file_data(meta_data, data_port_m, "output_data_port",
                                                             data_port_m.data_port.data_port_id)
          for outcome_m in self.outcomes:
              self._copy_element_meta_data_to_meta_file_data(meta_data, outcome_m, "outcome",
                                                             outcome_m.outcome.outcome_id)
  
          self._copy_element_meta_data_to_meta_file_data(meta_data, self.income, "income", "")