Delete un-picklable attribute _xp
Delete un-picklable attribute _xp

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