class_docstr: Elementwise sum the output of a submodule to its input 
class_docstr_tok: ["Elementwise","sum","the","output","of","a","submodule","to","its","input"]
code: def forward(self, x):
      output = x + self.sub(x)
      return output
  
imports: from collections import OrderedDict
  import math
  import torch
  import torch.nn
  import torch.nn.functional
label_desc: Use image node_id 2 for calling the ShortcutBlock obj's underlying member method code with example usage: obj.forward(x) and returns: output