Remove unused variable
Remove unused variable

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