code: def test_convert():
      assert pixel(ImageMath.eval("convert(A+B, 'L')", images)) == "L 3"
      assert pixel(ImageMath.eval("convert(A+B, '1')", images)) == "1 0"
      assert (
          pixel(ImageMath.eval("convert(A+B, 'RGB')", images))
          == "RGB (3, 3, 3)"
      )
  
imports: import pytest
  from PIL import Image, ImageMath
label_desc: Use image node_id 6 for calling a global function with example usage: test_convert() without return types