code: def assert_img_equal(A, B):
      assert img_to_string(A) == img_to_string(B)
  
imports: import pytest
  from PIL import Image, ImageMorph, _imagingmorph
  from .helper import assert_image_equal_tofile, hopper
label_desc: Use image node_id 4 for calling a global function with example usage: assert_img_equal(A, B) without return types