def load_iter(self, key, chunksize=None, noexpire=None):
return chunk_iterator(self.load_fd(key, noexpire=noexpire),<EOL>chunksize=chunksize)<EOL>
Lookup an item in the cache and return an iterator
        that reads chunksize bytes of data at a time.  The underlying
        file will be closed when all data has been read