class_docstr: See function `unbind`
code: def backward(cls, ctx, *tensors: torch.Tensor):
      return _stack_fw(tensors, ctx.dim), None
  
file_path: xformers/xformers/ops/unbind.py
imports: from typing import List, Optional, Sequence, Tuple, Union
  import torch
  from .common import _get_storage_base
label_desc: Use image node_id 2 for calling the _Unbind obj's underlying member method code with example usage: obj.backward(cls, ctx) and returns: _stack_fw,  None