code: def assign_bus_results(grid, bus_data):
      
  
      # iterate of nodes and assign voltage obtained from power flow analysis
      for node in grid._graph.nodes():
          # check if node is connected to graph
          if (node not in grid.graph_isolated_nodes()
              and not isinstance(node,
                                 LVLoadAreaCentreDing0)):
              if isinstance(node, LVStationDing0):
                  node.voltage_res = bus_data.loc[node.pypsa_id, 'v_mag_pu']
              elif isinstance(node, (LVStationDing0, LVLoadAreaCentreDing0)):
                  if node.lv_load_area.is_aggregated:
                      node.voltage_res = bus_data.loc[node.pypsa_id, 'v_mag_pu']
              elif not isinstance(node, CircuitBreakerDing0):
                  node.voltage_res = bus_data.loc[node.pypsa_id, 'v_mag_pu']
              else:
                  logger.warning("Object {} has been skipped while importing "
                                 "results!")
docs: Write results obtained from PF to graph
  
      Parameters
      ----------
      grid: ding0.network
      bus_data: pandas.DataFrame
          DataFrame containing voltage levels obtained from PF analysis