code: def backward(ctx, grad_outputs):
      return (
          ctx.backward_trans_func(
              grad_outputs, ctx.dist_spec, ctx.old_dist_spec, ctx.pg
          ),
          None,
          None,
          None,
          None,
          None,
      )
  
imports: from contextlib import contextmanager
  import torch
  import torch.distributed
  from numpy import prod
  from colossalai.legacy.tensor.distspec import DistPlacementPattern, _DistSpec
  from colossalai.legacy.tensor.process_group import ProcessGroup
label_desc: Use image node_id 2 for calling the TransformDistSpec obj's underlying member method code with example usage: obj.backward(ctx, grad_outputs) and returns: ctx,  None,  None,  None,  None,  None