code: def step_impl_compare_two_png_images(context):
      """Compare two PNG image files."""
      if context.area == "-":
          ref_filename = context.composite + ".png"
      else:
          ref_filename = context.composite + "_" + context.area + ".png"
      ref_filename = os.path.join(
          context.data_path, "ref", ref_filename
      )
      assert os.path.exists(ref_filename), "Missing reference file."
      assert_images_match(ref_filename, context.new_filename)
      os.remove(context.new_filename)
  
file_path: satpy/satpy/tests/features/steps/steps-real-load-process-write.py
imports: import fnmatch
  import os
  from tempfile import NamedTemporaryFile
  import numpy
  from behave import given, then, when
  from PIL import Image
label_desc: Use image node_id 9 for calling a global function with example usage: step_impl_compare_two_png_images(context) without return types