deal with the case when slices = []
deal with the case when slices = []

jnishi/chainer,jnishi/chainer,chainer/chainer,ronekko/chainer,wkentaro/chainer,pfnet/chainer,cupy/cupy,anaruse/chainer,keisuke-umezawa/chainer,okuta/chainer,ysekky/chainer,hvy/chainer,wkentaro/chainer,niboshi/chainer,niboshi/chainer,jnishi/chainer,kiyukuta/chainer,keisuke-umezawa/chainer,wkentaro/chainer,keisuke-umezawa/chainer,okuta/chainer,chainer/chainer,ktnyt/chainer,aonotas/chainer,kashif/chainer,okuta/chainer,keisuke-umezawa/chainer,cupy/cupy,cupy/cupy,hvy/chainer,hvy/chainer,hvy/chainer,okuta/chainer,ktnyt/chainer,chainer/chainer,cupy/cupy,niboshi/chainer,rezoo/chainer,ktnyt/chainer,ktnyt/chainer,tkerola/chainer,delta2323/chainer,chainer/chainer,jnishi/chainer,wkentaro/chainer,niboshi/chainer