code: def test_write_newmetadata():
      img = gi.GiftiImage()
      newmeta = gi.GiftiMetaData(mykey="val1")
      img.meta = newmeta
      myme = img.meta
      assert "mykey" in myme
      newmeta = gi.GiftiMetaData({"mykey1": "val2"})
      img.meta = newmeta
      myme = img.meta
      assert "mykey1" in myme
      assert "mykey" not in myme
  
imports: import shutil
  import sys
  import warnings
  from os.path import basename, dirname
  from os.path import join
  from unittest import mock
  import numpy
  import pytest
  from numpy.testing import assert_array_almost_equal
  from ...loadsave import load, save
  from ...nifti1 import xform_codes
  from ...testing import clear_and_catch_warnings, suppress_warnings
  from ...tmpdirs import InTemporaryDirectory
  from ..None import gifti
  from ..parse_gifti_fast import GiftiImageParser, GiftiParseError
  from ..util import gifti_endian_codes
label_desc: Use image node_id 13 for calling a global function with example usage: test_write_newmetadata() without return types