[Python] how to split an iterable in constant-size chunks [duplicate]

I am surprised I could not find a "batch" function that would take as input an iterable and return an iterable of iterables.

For example:

for i in batch(range(0,10), 1): print i
[0]
[1]
...
[9]


or:

for i in batch(range(0,10), 3): print i
[0,1,2]
[3,4,5]
[6,7,8]
[9]


Now, I wrote what I thought was a pretty simple generator:

def batch(iterable, n = 1):
current_batch = []
for item in iterable:
current_batch.append(item)
if len(current_batch) == n:
yield current_batch
current_batch = []
if current_batch:
yield current_batch


But the above does not give me what I would have expected:

for x in batch(range(0,10),3): print x
[0]
[0, 1]
[0, 1, 2]
[3]
[3, 4]
[3, 4, 5]
[6]
[6, 7]
[6, 7, 8]
[9]


So, I have missed something and this probably shows my complete lack of understanding of python generators. Anyone would care to point me in the right direction ?

[Edit: I eventually realized that the above behavior happens only when I run this within ipython rather than python itself]

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