Fix for flake8
Fix for flake8

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