code: def test_16bit_lut():
      """Tests for 16 bit -> 8 bit lut for converting I->L images
      see https://github.com/python-pillow/Pillow/issues/440
      """
      im = hopper("I")
      im.point(list(range(256)) * 256, "L")
  
imports: import pytest
  from .helper import assert_image_equal, hopper
label_desc: Use image node_id 2 for calling a global function with example usage: test_16bit_lut() without return types