code: @SuppressWarnings("unchecked")
    public <K extends IncompleteKey> FullEntity<K> getEntity(String name) {
      return ((Value<FullEntity<K>>) getValue(name)).get();
    }
docs: Returns the property value as an entity.
  
  @throws DatastoreException if no such property
  @throws ClassCastException if value is not an entity