code: def test_trns_p(self, tmp_path):
      # Check writing a transparency of 0, issue #528
      im = hopper("P")
      im.info["transparency"] = 0
  
      f = str(tmp_path / "temp.png")
      im.save(f)
  
      with Image.open(f) as im2:
          assert "transparency" in im2.info
  
          assert_image_equal(im2.convert("RGBA"), im.convert("RGBA"))
  
imports: import re
  import sys
  import zlib
  from io import BytesIO
  import pytest
  from PIL import Image, ImageFile, PngImagePlugin, features
  from .helper import PillowLeakTestCase, assert_image, assert_image_equal, assert_image_equal_tofile, hopper, is_win32, mark_if_feature_version, skip_unless_feature
label_desc: Use image node_id 28 for calling the TestFilePng obj's underlying member method code with example usage: obj.test_trns_p(tmp_path) without return types