code: def get_chunks(self, filename):
      chunks = []
      with open(filename, "rb") as fp:
          fp.read(8)
          with PngImagePlugin.PngStream(fp) as png:
              while True:
                  cid, pos, length = png.read()
                  chunks.append(cid)
                  try:
                      s = png.call(cid, pos, length)
                  except EOFError:
                      break
                  png.crc(cid, s)
      return chunks
  
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 1 for calling the TestFilePng obj's underlying member method code with example usage: obj.get_chunks(filename) and returns: chunks