code: def loss_example(pred, true):
      if cfg.model.loss_fun == "smoothl1":
          l1_loss = torch.nn.SmoothL1Loss()
          loss = l1_loss(pred, true)
          return loss, pred
  
label_desc: Use image node_id 1 for calling a global function with example usage: loss_example(pred, true) and returns: loss,  pred