def _makeCodebook(self,data,ncodes=128):
        [centroids, membership] = cluster.kmeans2(data,ncodes, minit='points')
        return(centroids)
Writes the output a blobkey property (or the blob contents) to the
dataset/ETHPy150Open sightmachine/SimpleCV/SimpleCV/Features/BOFFeatureExtractor.py/BOFFeatureExtractor._makeCodebook--crossover with--dataset/ETHPy150Open jahlborn/appengine-rest-server/src/main/python/rest/__init__.py/BlobReferenceHandler.value_to_response