edit __init__.py
from chainer_chemistry.dataset.splitters import base_splitter # NOQA
from chainer_chemistry.dataset.splitters import random_splitter # NOQA
+from chainer_chemistry.dataset.splitters import scaffold_splitter # NOQA
from chainer_chemistry.dataset.splitters import stratified_splitter # NOQA
from chainer_chemistry.dataset.splitters.base_splitter import BaseSplitter # NOQA
from chainer_chemistry.dataset.splitters.random_splitter import RandomSplitter # NOQA
+from chainer_chemistry.dataset.splitters.scaffold_splitter import ScaffoldSplitter # NOQA
from chainer_chemistry.dataset.splitters.stratified_splitter import StratifiedSplitter # NOQA
