code: def test_single_image():
      # Check we can use a single image as argument
      R = SpaceTimeRealign(
          IM, tr=3, slice_times="ascending", slice_info=2
      )
      R.estimate(
          refscan=None, loops=1, between_loops=1, optimizer="steepest"
      )
      R = SpaceRealign(IM)
      R.estimate(
          refscan=None, loops=1, between_loops=1, optimizer="steepest"
      )
      R = Realign4d(IM, 3, [0, 1, 2], (2, 1))
      R.estimate(
          refscan=None, loops=1, between_loops=1, optimizer="steepest"
      )
  
imports: import warnings
  import nibabel
  import numpy
  import pytest
  from nibabel import io_orientation
  from numpy.testing import assert_array_almost_equal, assert_array_equal
  from ....None import load_image
  from ....core.image.image_spaces import make_xyz_image, xyz_affine
  from ....io.nibcompat import get_header
  from ....testing import funcfile
  from ...slicetiming.timefuncs import st_02413, st_42031, st_43210
  from ..affine import Rigid
  from ..groupwise_registration import FmriRealign4d, Image4d, Realign4d, Realign4dAlgorithm, SpaceRealign, SpaceTimeRealign, make_grid, resample4d
label_desc: Use image node_id 25 for calling a global function with example usage: test_single_image() without return types