code: def test_xyres_tiff(self):
      filename = "Tests/images/pil168.tif"
      with Image.open(filename) as im:
          # legacy api
          assert isinstance(im.tag[X_RESOLUTION][0], tuple)
          assert isinstance(im.tag[Y_RESOLUTION][0], tuple)
  
          # v2 api
          assert isinstance(
              im.tag_v2[X_RESOLUTION], TiffImagePlugin.IFDRational
          )
          assert isinstance(
              im.tag_v2[Y_RESOLUTION], TiffImagePlugin.IFDRational
          )
  
          assert im.info["dpi"] == (72.0, 72.0)
  
imports: import os
  from io import BytesIO
  import pytest
  from PIL import Image, ImageFile, TiffImagePlugin
  from PIL.TiffImagePlugin import RESOLUTION_UNIT, X_RESOLUTION, Y_RESOLUTION
  from .helper import assert_image_equal, assert_image_equal_tofile, assert_image_similar, assert_image_similar_tofile, hopper, is_pypy, is_win32
label_desc: Use image node_id 8 for calling the TestFileTiff obj's underlying member method code with example usage: obj.test_xyres_tiff() without return types