code: def callback_CC(sdr, status):
      # Status indicates at which stage of the optimization we currently are
      # For now, we will only react at the end of each resolution of the scale
      # space
      if status == imwarp.RegistrationStages.SCALE_END:
          # get the current images from the metric
          wmoving = sdr.metric.moving_image
          wstatic = sdr.metric.static_image
          # draw the images on top of each other with different colors
          regtools.overlay_images(
              wmoving,
              wstatic,
              "Warped moving",
              "Overlay",
              "Warped static",
          )
  
file_path: dipy/doc/examples/syn_registration_2d.py
imports: import numpy
  from dipy.align.imwarp import SymmetricDiffeomorphicRegistration
  from dipy.align.metrics import SSDMetric, CCMetric
  import dipy.align.imwarp
  from dipy.data import get_fnames
  from dipy.io.image import load_nifti_data
  from dipy.segment.mask import median_otsu
  from dipy.viz import regtools
label_desc: Use image node_id 1 for calling a global function with example usage: callback_CC(sdr, status) without return types