class_docstr: Gather tensors from all workers with support for backward propagation:
  This implementation does not cut the gradients as torch.distributed.all_gather does.
code: def forward(ctx, x):
      output = [
          torch.zeros_like(x) for _ in range(dist.get_world_size())
      ]
      dist.all_gather(output, x)
      return tuple(output)
  
imports: import contextlib
  import logging
  import os
  import pickle
  import socket
  import subprocess
  import warnings
  from itertools import chain
  import torch
  from mmf.common.registry import registry
  from torch import distributed
label_desc: Use image node_id 1 for calling the GatherLayer obj's underlying member method code with example usage: obj.forward(ctx, x) and returns: tuple