code: def read_seg(self, parc_type='aparc'):
          
          seg_file = self.dir / 'mri' / (parc_type + '+aseg.mgz')
          seg_mri = load(seg_file)
          seg_aff = seg_mri.affine
          seg_dat = seg_mri.get_data()
          return seg_dat, seg_aff
docs: Read the MRI segmentation.
  
          Parameters
          ----------
          parc_type : str
              'aparc' or 'aparc.a2009s'
  
          Returns
          -------
          numpy.ndarray
              3d matrix with values
          numpy.ndarray
              4x4 affine matrix