code: def to_nibabel(image):
      
      if image.dimension != 3:
          raise ValueError('Only 3D images currently supported')
  
      import nibabel as nib
      array_data = image.numpy()
      affine = np.hstack([image.direction*np.diag(image.spacing),np.array(image.origin).reshape(3,1)])
      affine = np.vstack([affine, np.array([0,0,0,1.])])
      affine[:2,:] *= -1
      new_img = nib.Nifti1Image(array_data, affine)
      return new_img
docs: Convert an ANTsImage to a Nibabel image