code: def transformer(grid):
      
  
      # choose size and amount of transformers
      transformer, transformer_cnt = select_transformers(grid)
  
      # create transformers and add them to station of LVGD
      for t in range(0, transformer_cnt):
          lv_transformer = TransformerDing0(
              grid=grid,
              id_db=id,
              v_level=0.4,
              s_max_longterm=transformer['S_nom'],
              r=transformer['R'],
              x=transformer['X'])
  
          # add each transformer to its station
          grid._station.add_transformer(lv_transformer)
docs: Choose transformer and add to grid's station
  
      Parameters
      ----------
      grid: LVGridDing0
          LV grid data