code: def forward(ctx: "Join", input: Tensor, phony: Tensor) -> Tensor:  # type: ignore
      return input.detach()
  
file_path: fairscale/fairscale/nn/pipe/dependency.py
imports: from typing import List, Tuple
  import torch
  from torch import Tensor
  from .phony import get_phony
label_desc: Use image node_id 1 for calling the Join obj's underlying member method code with example usage: obj.forward(ctx, input, phony) and returns: input