import logging
import numpy as np

def new_iterator(data, n_jobs, batch_size, repeat=True, shuffle=True, n_prefetch=2):
	from chainer.iterators import SerialIterator, MultiprocessIterator

	if n_jobs > 0:
		it = MultiprocessIterator(data,
			n_processes=n_jobs,
			n_prefetch=n_prefetch,
			batch_size=batch_size,
			repeat=repeat, shuffle=shuffle)
	else:
		it = SerialIterator(data,
			batch_size=batch_size,
			repeat=repeat, shuffle=shuffle)
	logging.info("Using {it.__class__.__name__} with batch size {it.batch_size}".format(it=it))
	n_batches = int(np.ceil(len(data) / it.batch_size))
	return it, n_batches