code: func getDefaultStorageClass(location string) (string, error) {
  	if _, ok := GCSMultiRegionalLocations[location]; ok {
  		return defaultMultiRegionalStorageClass, nil
  	}
  	if _, ok := GCSRegionalLocations[location]; ok {
  		return defaultRegionalStorageClass, nil
  	}
  	return "", ErrUnknownLocation
  }
docs: // getDefaultStorageClass returns the default StorageClass for a given location.
  // This takes into account regional/multi-regional incompatibility.
  //
  // Empty string is returned if the location cannot be matched.