code: private ChargingStation getChargingStation(ChargingStationId chargingStationId) {
          ChargingStation chargingStation = chargingStationRepository.findOne(chargingStationId.getId());
  
          if (chargingStation == null) {
              LOG.error("Could not find charging station {}", chargingStationId);
          }
  
          return chargingStation;
      }
docs: Tries to find a {@code ChargingStation} by the passed id, if not found an error will be logged and null will be
  returned.
  
  @param chargingStationId charging station identifier.
  @return charging station if found, null otherwise.