code: def forward(ctx, src, group, *tensors):
      ctx.src = src
      ctx.group = group
      assert all(t.size() == tensors[0].size() for t in tensors)
      output = torch.zeros_like(tensors[0])
      if dist.get_rank(group=group) == src:
          dist.scatter(output, list(tensors), src, group=group)
      else:
          dist.scatter(output, None, src, group=group)
      return output
  
imports: import torch
  import torch.distributed
  from torch.autograd import Function
label_desc: Use image node_id 1 for calling the _Scatter obj's underlying member method code with example usage: obj.forward(ctx, src, group) and returns: output