code: def test_brain_seg3():
      _test_brain_seg("4k", niters=3, beta=0.5, ngb_size=6)
  
imports: from numbers import Number
  import numpy
  from numpy.testing import assert_almost_equal, assert_array_almost_equal
  from ....io.files import load
  from ....testing import anatfile
  from ..brain_segmentation import BrainT1Segmentation
  from ..segmentation import Segmentation
label_desc: Use image node_id 5 for calling a global function with example usage: test_brain_seg3() without return types