def _blobs_page_start(iterator, page, response):
 page.prefixes = tuple(response.get('prefixes', ()))
 iterator.prefixes.update(page.prefixes)

def _blobs_page_start ( iterator , page , response ) : page . prefixes = tuple ( response . get ( 'prefixes' , ( ) ) ) iterator . prefixes . update ( page . prefixes )
grab prefixes after a :class:~google .