django queryset chunker

queryset_chunker.py

from sys import maxint
def queryset_chunker(queryset, chunksize=10000):
    pk = -maxint
    last_pk = queryset.order_by('-pk')[0][0]
    queryset = queryset.order_by('pk')
    while pk < last_pk:
        for row in queryset.filter(pk__gt=pk)[:chunksize]:
            pk = row[0]
            yield row