code: def test_shift_right(self):
      decoder_start_token_id = 0
      pad_token_id = 1
      labels = np.arange(2, 102).reshape(5, 20)
      labels[:2, 15:] = -100
  
      decoder_input_ids = shift_tokens_right(
          labels, pad_token_id, decoder_start_token_id
      )
      np_decoder_input_ids = np.array(decoder_input_ids)
  
      padded_slice = np_decoder_input_ids[:2, (15 + 1) :]
      self.assertTrue((padded_slice == 1).all())
  
      not_padded_slice = np_decoder_input_ids[2:, 1:]
      rolled_labels = np.roll(labels[2:], 1)[:, 1:]
      self.assertTrue((not_padded_slice == rolled_labels).all())
      self.assertTrue((np_decoder_input_ids[:, 0] == 0).all())
  
imports: import tempfile
  import unittest
  import numpy
  import transformers
  from transformers import is_flax_available
  from transformers.testing_utils import is_pt_flax_cross_test, require_flax, require_sentencepiece, require_tokenizers, slow
  from ...generation.test_flax_utils import FlaxGenerationTesterMixin
  from ...test_configuration_common import ConfigTester
  from ...test_modeling_flax_common import FlaxModelTesterMixin, ids_tensor
label_desc: Use image node_id 8 for calling the FlaxT5ModelTest obj's underlying member method code with example usage: obj.test_shift_right() without return types