code: def get_range_vector(size: int, device: int) -> torch.Tensor:
      
      if device > -1:
          return torch.cuda.LongTensor(size, device=device).fill_(1).cumsum(0) - 1
      else:
          return torch.arange(0, size, dtype=torch.long)
docs: Returns a range vector with the desired size, starting at 0. The CUDA implementation
      is meant to avoid copy data from CPU to GPU.