Avoid Variable(None) issues
Avoid Variable(None) issues

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