docs: def build_lv_grid_district(self,
                                 lv_load_area,
                                 lv_grid_districts,
                                 lv_stations):
          """Instantiates and associates lv_grid_district incl grid and station.
          
          The instantiation creates more or less empty objects including relevant
          data for transformer choice and grid creation
  
          Parameters
          ----------
          lv_load_area: :shapely:`Shapely Polygon object<polygons>`
              load_area object
          lv_grid_districts: :pandas:`pandas.DataFrame<dataframe>`
              Table containing lv_grid_districts of according load_area 
          lv_stations : :pandas:`pandas.DataFrame<dataframe>`
              Table containing lv_stations of according load_area
          """
  
          # There's no LVGD for current LA
          # -> TEMP WORKAROUND: Create single LVGD from LA, replace unknown valuess by zero
          # TODO: Fix #155 (see also: data_processing #68)
          if len(lv_grid_districts) == 0:
              # raise ValueError(
              #     'Load Area {} has no LVGD - please re-open #155'.format(
              #         repr(lv_load_area)))
              geom = wkt_dumps(lv_load_area.geo_area)
  
              lv_grid_districts = \
                  lv_grid_districts.append(
                      pd.DataFrame(
                          {'la_id': [lv_load_area.id_db],
                           'geom': [geom],
                           'population': [0],
  
                           'peak_load_residential': [lv_load_area.peak_load_residential],
                           'peak_load_retail': [lv_load_area.peak_load_retail],
                           'peak_load_industrial': [lv_load_area.peak_load_industrial],
                           'peak_load_agricultural': [lv_load_area.peak_load_agricultural],
  
                           'sector_count_residential': [0],
                           'sector_count_retail': [0],
                           'sector_count_industrial': [0],
                           'sector_count_agricultural': [0],
  
                           'sector_consumption_residential': [0],
                           'sector_consumption_retail': [0],
                           'sector_consumption_industrial': [0],
                           'sector_consumption_agricultural': [0]
                           },
                          index=[lv_load_area.id_db]
                      )
                  )
  
          lv_nominal_voltage = cfg_ding0.get('assumptions', 'lv_nominal_voltage')
  
          # Associate lv_grid_district to load_area
          for id, row in lv_grid_districts.iterrows():
              lv_grid_district = LVGridDistrictDing0(
                  id_db=id,
                  lv_load_area=lv_load_area,
                  geo_data=wkt_loads(row['geom']),
                  population=0 if isnan(row['population']) else int(row['population']),
                  peak_load_residential=row['peak_load_residential'],
                  peak_load_retail=row['peak_load_retail'],
                  peak_load_industrial=row['peak_load_industrial'],
                  peak_load_agricultural=row['peak_load_agricultural'],
                  peak_load=(row['peak_load_residential'] +
                                 row['peak_load_retail'] +
                                 row['peak_load_industrial'] +
                                 row['peak_load_agricultural']),
                  sector_count_residential=int(row['sector_count_residential']),
                  sector_count_retail=int(row['sector_count_retail']),
                  sector_count_industrial=int(row['sector_count_industrial']),
                  sector_count_agricultural=int(row['sector_count_agricultural']),
                  sector_consumption_residential=row[
                      'sector_consumption_residential'],
                  sector_consumption_retail=row['sector_consumption_retail'],
                  sector_consumption_industrial=row[
                      'sector_consumption_industrial'],
                  sector_consumption_agricultural=row[
                      'sector_consumption_agricultural'])
  
              # be aware, lv_grid takes grid district's geom!
              lv_grid = LVGridDing0(network=self,
                                    grid_district=lv_grid_district,
                                    id_db=id,
                                    geo_data=wkt_loads(row['geom']),
                                    v_level=lv_nominal_voltage)
  
              # create LV station
              lv_station = LVStationDing0(
                  id_db=id,
                  grid=lv_grid,
                  lv_load_area=lv_load_area,
                  geo_data=wkt_loads(lv_stations.loc[id, 'geom'])
                              if id in lv_stations.index.values
                              else lv_load_area.geo_centre,
                  peak_load=lv_grid_district.peak_load)
  
              # assign created objects
              # note: creation of LV grid is done separately,
              # see NetworkDing0.build_lv_grids()
              lv_grid.add_station(lv_station)
              lv_grid_district.lv_grid = lv_grid
              lv_load_area.add_lv_grid_district(lv_grid_district)