code: def fetch(data_filename):
      """Attempt to fetch data, but if unavailable, skip the tests."""
      try:
          return _fetch(data_filename)
      except (ConnectionError, ModuleNotFoundError):
          pytest.skip(
              f"Unable to download {data_filename}",
              allow_module_level=True,
          )
  
imports: import os
  import re
  import struct
  import threading
  import functools
  from tempfile import NamedTemporaryFile
  import numpy
  from numpy import testing
  from numpy.testing import TestCase, assert_, assert_warns, assert_no_warnings, assert_equal, assert_almost_equal, assert_array_equal, assert_allclose, assert_array_almost_equal, assert_array_almost_equal_nulp, assert_array_less
  import warnings
  from ..None import data, io
  from ..data._fetchers import _fetch
  from ..util import img_as_uint, img_as_float, img_as_int, img_as_ubyte
  from ._warnings import expected_warnings
  import pytest
label_desc: Use image node_id 9 for calling a global function with example usage: fetch(data_filename) and returns: _fetch