code: def test_isolation(self):
      # Test image isolated from external changes to affine
      img_klass = self.image_class
      arr, aff, hdr, sub_hdr, mlist = (
          self.img.get_fdata(),
          self.img.affine,
          self.img.header,
          self.img.get_subheaders(),
          self.img.get_mlist(),
      )
      img = img_klass(arr, aff, hdr, sub_hdr, mlist)
      assert_array_equal(img.affine, aff)
      aff[0, 0] = 99
      assert not np.all(img.affine == aff)
  
imports: import os
  import warnings
  from pathlib import Path
  from unittest import TestCase
  import numpy
  import pytest
  from numpy.testing import assert_array_almost_equal, assert_array_equal
  from ..ecat import EcatHeader, EcatImage, EcatSubHeader, get_frame_order, get_series_framenumbers, read_mlist
  from ..openers import Opener
  from ..testing import data_path, suppress_warnings
  from ..tmpdirs import InTemporaryDirectory
  from .None import test_wrapstruct
  from .test_fileslice import slicer_samples
label_desc: Use image node_id 6 for calling the TestEcatImage obj's underlying member method code with example usage: obj.test_isolation() without return types