remove redundant parentheses
remove redundant parentheses

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