input: Write a python function to normalize image data by dividing by 255.0 and check its effect using assert statements.
  assert (normalize_images([[[[0, 128, 255]]]]) == [[[[0.0, 0.5019608, 1.0]]]]).all()
  assert (normalize_images([[[[255, 255, 255], [128, 128, 128]]]]) == [[[[1.0, 1.0, 1.0], [0.5019608, 0.5019608, 0.5019608]]]]).all()
  assert (normalize_images([[[[0, 0, 0], [255, 255, 255]]]]) == [[[[0.0, 0.0, 0.0], [1.0, 1.0, 1.0]]]]).all()
output: def normalize_images(images):
      import numpy as np
      return np.array(images) / 255.0