code: def lighting_list(imgs, alphastd, eigval, eigvec, alpha=None):
      """
      Perform AlexNet-style PCA jitter on the given list of images.
      Args:
          images (list): list of images to perform lighting jitter.
          alphastd (float): jitter ratio for PCA jitter.
          eigval (list): eigenvalues for PCA jitter.
          eigvec (list[list]): eigenvectors for PCA jitter.
      Returns:
          out_images (list): the list of jittered images.
      """
      if alphastd == 0:
          return imgs
      # generate alpha1, alpha2, alpha3
      alpha = np.random.normal(0, alphastd, size=(1, 3))
      eig_vec = np.array(eigvec)
      eig_val = np.reshape(eigval, (1, 3))
      rgb = np.sum(
          eig_vec
          * np.repeat(alpha, 3, axis=0)
          * np.repeat(eig_val, 3, axis=0),
          axis=1,
      )
      out_images = []
      for img in imgs:
          for idx in range(img.shape[0]):
              img[idx] = img[idx] + rgb[2 - idx]
          out_images.append(img)
      return out_images
  
imports: import math
  import numpy
  import cv2
label_desc: Use image node_id 10 for calling a global function with example usage: lighting_list(imgs, alphastd, eigval, eigvec, alpha) and returns: out_images, imgs