code: def compute_loss(pred, true):
      """Compute loss and prediction score.
  
      Args:
          pred (torch.tensor): Unnormalized prediction
          true (torch.tensor): Grou
  
      Returns: Loss, normalized prediction score
  
      """
      bce_loss = torch.nn.BCEWithLogitsLoss(
          reduction=cfg.model.size_average
      )
      mse_loss = torch.nn.MSELoss(reduction=cfg.model.size_average)
  
      # default manipulation for pred and true
      # can be skipped if special loss computation is needed
      pred = pred.squeeze(-1) if pred.ndim > 1 else pred
      true = true.squeeze(-1) if true.ndim > 1 else true
  
      # Try to load customized loss
      for func in register.loss_dict.values():
          value = func(pred, true)
          if value is not None:
              return value
  
      if cfg.model.loss_fun == "cross_entropy":
          # multiclass
          if pred.ndim > 1 and true.ndim == 1:
              pred = F.log_softmax(pred, dim=-1)
              return F.nll_loss(pred, true), pred
          # binary or multilabel
          else:
              true = true.float()
              return bce_loss(pred, true), torch.sigmoid(pred)
      elif cfg.model.loss_fun == "mse":
          true = true.float()
          return mse_loss(pred, true), pred
      else:
          raise ValueError(
              f"Loss function '{cfg.model.loss_fun}' not supported"
          )
  
imports: import torch
  import torch.nn.functional
  import torch_geometric.graphgym.register
  from torch_geometric.graphgym.config import cfg
label_desc: Use image node_id 1 for calling a global function with example usage: compute_loss(pred, true) and returns: value, F,  pred, bce_loss,  torch, mse_loss,  pred