code: def combine_images(
      img1: np.ndarray, img2: np.ndarray, alpha=0.5
  ) -> np.ndarray:
      """
      Combine two Numpy arrays of the same shape
  
      :param img1: a Numpy array
      :param img2: a Numpy array
      :param alpha: percentage weight for the first image
      :return: The combined image
      """
      return alpha * img1 + (1 - alpha) * img2
  
file_path: adversarial-robustness-toolbox/art/estimators/poison_mitigation/strip/strip.py
imports: from __future__ import absolute_import, division, print_function, unicode_literals
  import logging
  from typing import Callable, Optional
  import numpy
  from scipy.stats import entropy, norm
  from tqdm.auto import tqdm
  from art.estimators.certification.abstain import AbstainPredictorMixin
label_desc: Use image node_id 1 for calling a global function with example usage: combine_images(img1, img2, alpha) and returns: unknown