code: def test_rgba():
      # Created with ImageMagick:
      # convert transparent.png -compress None transparent.sgi
      test_file = "Tests/images/transparent.sgi"
  
      with Image.open(test_file) as im:
          assert_image_equal_tofile(im, "Tests/images/transparent.png")
          assert im.get_format_mimetype() == "image/sgi"
  
file_path: pillow/Tests/test_file_sgi.py
imports: from __future__ import annotations
  import pytest
  from PIL import Image, SgiImagePlugin
  from .helper import assert_image_equal, assert_image_equal_tofile, assert_image_similar, hopper
label_desc: Use image node_id 4 for calling a global function with example usage: test_rgba() without return types