code: def test_offset(self):
      # Test get / set offset
      hdr = self.header_class()
      offset = hdr.get_data_offset()
      hdr.set_data_offset(offset + 16)
      assert hdr.get_data_offset() == offset + 16
  
imports: import itertools
  import logging
  import os
  import pickle
  import re
  from io import BytesIO, StringIO
  import numpy
  import pytest
  from numpy.testing import assert_array_almost_equal, assert_array_equal
  from ..None import imageglobals
  from ..analyze import AnalyzeHeader, AnalyzeImage
  from ..arraywriters import WriterError
  from ..casting import sctypes_aliases
  from ..nifti1 import Nifti1Header
  from ..optpkg import optional_package
  from ..spatialimages import HeaderDataError, HeaderTypeError, supported_np_types
  from ..testing import assert_dt_equal, bytesio_filemap, bytesio_round_trip, data_path, suppress_warnings
  from ..tmpdirs import InTemporaryDirectory
  from .None import test_spatialimages
  from .None import test_wrapstruct
label_desc: Use image node_id 17 for calling the TestAnalyzeHeader obj's underlying member method code with example usage: obj.test_offset() without return types