code: def delete_multi_async(blob_keys, **options):
    
    if isinstance(blob_keys, (basestring, BlobKey)):
      raise TypeError('Expected a list, got %r' % (blob_key,))
    rpc = blobstore.create_rpc(**options)
    yield blobstore.delete_async(blob_keys, rpc=rpc)
docs: Async version of delete_multi().