code: def get_confidence_aggregation_bank():
      """Generate a dictionary with confidence aggregation functions.
  
      Supported confidence aggregation functions:
          min: minimum
          max: maximum
          mean: arithmetic mean
          prod: product
  
      Returns:
          dictionary with functions.
      """
      confidence_aggregation_bank = {
          "mean": lambda x: sum(x) / len(x),
          "min": min,
          "max": max,
      }
      # python 3.7 and earlier do not have math.prod
      if hasattr(math, "prod"):
          confidence_aggregation_bank["prod"] = math.prod
      else:
          import operator
          from functools import reduce
  
          confidence_aggregation_bank["prod"] = lambda x: reduce(
              operator.mul, x, 1
          )
      return confidence_aggregation_bank
  
imports: import math
  from abc import ABC, abstractmethod
  from dataclasses import dataclass, field
  from functools import partial
  from typing import List, Optional
  import torch
  from omegaconf import DictConfig, OmegaConf
  from nemo.collections.asr.parts.utils.rnnt_utils import Hypothesis
  from nemo.utils import logging
label_desc: Use image node_id 2 for calling a global function with example usage: get_confidence_aggregation_bank() and returns: confidence_aggregation_bank