text: """
  This is a tutorial example.
  """
  import tensorflow as tf
  import labelreg.utils as util
  
  
  def warp_volumes_by_ddf(input_, ddf):
      grid_warped = util.get_reference_grid(ddf.shape[1:4]) + ddf
      warped = util.resample_linear(tf.convert_to_tensor(input_, dtype=tf.float32), grid_warped)
      with tf.Session() as sess:
          return sess.run(warped)
  