code: def simple_callback(sdr, status):
      r"""Verify callback function is called from SyN"""
      if status == imwarp.RegistrationStages.INIT_START:
          sdr.INIT_START_CALLED = 1
      if status == imwarp.RegistrationStages.INIT_END:
          sdr.INIT_END_CALLED = 1
      if status == imwarp.RegistrationStages.OPT_START:
          sdr.OPT_START_CALLED = 1
      if status == imwarp.RegistrationStages.OPT_END:
          sdr.OPT_END_CALLED = 1
      if status == imwarp.RegistrationStages.SCALE_START:
          sdr.SCALE_START_CALLED = 1
      if status == imwarp.RegistrationStages.SCALE_END:
          sdr.SCALE_END_CALLED = 1
      if status == imwarp.RegistrationStages.ITER_START:
          sdr.ITER_START_CALLED = 1
      if status == imwarp.RegistrationStages.ITER_END:
          sdr.ITER_END_CALLED = 1
  
imports: import numpy
  import nibabel.eulerangles
  from numpy.testing import assert_equal, assert_array_equal, assert_array_almost_equal, assert_raises
  from dipy.core.interpolation import interpolate_scalar_2d, interpolate_scalar_3d
  from dipy.data import get_fnames
  from dipy.align import floating
  from dipy.align import imwarp
  from dipy.align import metrics
  from dipy.align import vector_fields
  from dipy.align import VerbosityLevels
  from dipy.align.imwarp import DiffeomorphicMap
  from dipy.tracking.streamline import deform_streamlines
  from dipy.testing.decorators import set_random_number_generator
label_desc: Use image node_id 7 for calling a global function with example usage: simple_callback(sdr, status) without return types