code: def test_registered_extensions(self):
      # Arrange
      # Open an image to trigger plugin registration
      with Image.open("Tests/images/rgb.jpg"):
          pass
  
      # Act
      extensions = Image.registered_extensions()
  
      # Assert
      assert extensions
      for ext in [".cur", ".icns", ".tif", ".tiff"]:
          assert ext in extensions
  
imports: import io
  import os
  import shutil
  import sys
  import tempfile
  import pytest
  from PIL import Image, ImageDraw, ImagePalette, UnidentifiedImageError
  from .helper import assert_image_equal, assert_image_equal_tofile, assert_image_similar_tofile, assert_not_all_same, hopper, is_win32, mark_if_feature_version, skip_unless_feature
label_desc: Use image node_id 28 for calling the TestImage obj's underlying member method code with example usage: obj.test_registered_extensions() without return types