code: def get_cross_entropy(obs: np.array, ref: np.array) -> float:
      """
      Returns the cross entropy between two probability distributions.
      https://en.wikipedia.org/wiki/Cross_entropy
  
      :param obs: The observed probability distribution.
      :type obs: np.array
      :param ref: The reference probability distribution.
      :type ref: np.array
      :return: The cross entropy between the two probability distributions.
      :rtype: float
      """
      return -np.sum(ref * np.log2(obs))
  
file_path: responsible-ai-toolbox/responsibleai/responsibleai/databalanceanalysis/distribution_balance_measures.py
imports: from typing import Callable, Dict, List
  import numpy
  import pandas
  import scipy
  from responsibleai.databalanceanalysis.balance_measures import BalanceMeasures
  from responsibleai.databalanceanalysis.constants import Constants, Measures
label_desc: Use image node_id 1 for calling a global function with example usage: get_cross_entropy(obs, ref) and returns: unknown