code: def test_resampling_warning_s_form(affine_eye, shape, rng):
      data = rng.integers(0, 10, shape, dtype="int32")
      img_no_sform = Nifti1Image(data, affine_eye)
      img_no_sform.set_sform(None)
  
      with pytest.warns(
          Warning, match="The provided image has no sform"
      ):
          resample_img(img_no_sform, target_affine=affine_eye)
  
imports: import copy
  import math
  import os
  from pathlib import Path
  import numpy
  import pytest
  from nibabel import Nifti1Header, Nifti1Image
  from nibabel.freesurfer import MGHImage
  from numpy.testing import assert_allclose, assert_almost_equal, assert_array_almost_equal, assert_array_equal, assert_equal
  from nilearn import _utils
  from nilearn._utils import testing
  from nilearn.conftest import _affine_eye, _rng
  from nilearn.image import get_data
  from nilearn.image.image import _pad_array, crop_img
  from nilearn.image.resampling import BoundingBoxError, coord_transform, from_matrix_vector, get_bounds, reorder_img, resample_img, resample_to_img
label_desc: Use image node_id 13 for calling a global function with example usage: test_resampling_warning_s_form(affine_eye, shape, rng) without return types