Fix doctest
Fix doctest

ronekko/chainer,chainer/chainer,niboshi/chainer,ktnyt/chainer,chainer/chainer,anaruse/chainer,wkentaro/chainer,jnishi/chainer,keisuke-umezawa/chainer,rezoo/chainer,ktnyt/chainer,hvy/chainer,okuta/chainer,ktnyt/chainer,wkentaro/chainer,hvy/chainer,ktnyt/chainer,keisuke-umezawa/chainer,pfnet/chainer,niboshi/chainer,hvy/chainer,okuta/chainer,keisuke-umezawa/chainer,okuta/chainer,jnishi/chainer,wkentaro/chainer,wkentaro/chainer,chainer/chainer,niboshi/chainer,niboshi/chainer,okuta/chainer,chainer/chainer,hvy/chainer,tkerola/chainer,jnishi/chainer,keisuke-umezawa/chainer,jnishi/chainer