Yield n successive chunks from l.

def chunks(l, n):
    """ Yield n successive chunks from l.
    """
    newn = int(1.0 * len(l) / n + 0.5)
    for i in range(0, n - 1):
        yield l[i * newn:i * newn + newn]
    yield l[n * newn - newn:]