class ListChunk:
    def __init__(self, items, chunksize):
        self.items = items
        self.chunksize = chunksize
        self.ii = 0
    def __iter__(self):
        return self
    def next(self):
        if self.ii >= len(self.items):
            raise StopIteration
        tmp = self.items[self.ii:self.ii + self.chunksize]
        self.ii = self.ii + self.chunksize
        return tmp

items = ListChunk([1,2,3,4,5,5,6,7,8], 2)
for slice in items:
    print slice