code: def test_as_image():
      # test image creation / pass through function
      img = as_image(funcfile)  # string filename
      img1 = as_image(funcfile)  # unicode
      img2 = as_image(img)
      assert_array_equal(img.affine, img1.affine)
      assert_array_equal(img.get_fdata(), img1.get_fdata())
      assert img is img2
  
imports: from os.path import dirname
  from os.path import join
  import nibabel
  import numpy
  import pytest
  from nibabel import Nifti1Header
  from nibabel.filebasedimages import ImageFileError
  from nibabel.spatialimages import HeaderDataError
  from nibabel.tests.test_round_trip import big_bad_ulp
  from nipy.core.api import AffineTransform
  from nipy.core.api import Image, vox2mni
  from nipy.testing import anatfile, assert_almost_equal, assert_array_almost_equal, assert_array_equal, funcfile
  from nipy.testing.decorators import if_templates
  from nipy.utils import DataError, templates
  from ..api import as_image, load_image, save_image
label_desc: Use image node_id 12 for calling a global function with example usage: test_as_image() without return types