code: @Override
  	public <E> AppEngineDelete<E> delete(Metamodel<E> metamodel) {
  		if (metamodel == null) {
  			throw new IllegalArgumentException("'metamodel' must not be [" + metamodel + "]");
  		}
  		
  		return new AppEngineDelete<E>(metamodel, this);
  	}
docs: Returns {@code Delete} command based on App Engine Low-level Datastore
  API for the specified entity metamodel.
  This method is the entry point for deleting Command Builder API.
  
  @param <E> The type of entity deleted by this {@code Delete}.
  @param metamodel The metamodel of the entity deleted by this
  {@code Delete}.
  @return The {@code Delete} for the specified entity metamodel.