code: def forward(self, input):
      return input
  
imports: from torch import nn
  from fairscale.nn.pipe.skip import Namespace, pop, skippable, stash
  from fairscale.nn.pipe.skip.layout import inspect_skip_layout
label_desc: Use image node_id 1 for calling the Pass obj's underlying member method code with example usage: obj.forward(input) and returns: input