code: def swap_dist_out_slate(idx):
      return np.sum(x - i for i, x in enumerate(idx))
  
imports: import logging
  from itertools import permutations
  from typing import List, Optional
  import numpy
  import reagent.core.types
  import torch
  import torch.nn
  from reagent.core.dataclasses import field
  from reagent.core.parameters import Seq2SlateParameters
  from reagent.core.torch_utils import gather
  from reagent.models.seq2slate import BaselineNet, Seq2SlateMode, Seq2SlateTransformerNet
  from reagent.optimizer.union import Optimizer__Union
  from reagent.training.ranking.seq2slate_trainer import Seq2SlateTrainer
label_desc: Use image node_id 3 for calling a global function with example usage: swap_dist_out_slate(idx) and returns: np