def unmap(self, data, count, inds, fill=0):
        """Unmap a subset of item (data) back to the original set of items (of size
        count)"""
        if data.dim() == 1:
            ret = paddle.full((count,1), fill, dtype=data.dtype)
            data=data.unsqueeze(0).transpose((1,0))
            ret[inds,:] = data
            ret=ret.transpose((1,0)).squeeze()
        else:
            new_size = (count, ) + tuple(data.shape[1:])
            ret = paddle.full(new_size, fill, dtype=data.dtype)
            ret[inds.astype(paddle.bool), :] = data
        return ret
Unmap a subset of item (data) back to the original set of items (of size
        count)
ppdet/modeling/heads/co_atss_head.py