code: def test_shift_tokens_right(self):
      input_ids = np.array(
          [[71, 82, 18, 33, 2, 1, 1], [68, 34, 26, 58, 30, 82, 2]],
          dtype=np.int64,
      )
      shifted = shift_tokens_right(input_ids, 1)
      n_pad_before = np.equal(input_ids, 1).astype(np.float32).sum()
      n_pad_after = np.equal(shifted, 1).astype(np.float32).sum()
      self.assertEqual(shifted.shape, input_ids.shape)
      self.assertEqual(n_pad_after, n_pad_before - 1)
      self.assertTrue(np.equal(shifted[:, 0], 2).all())
  
imports: import unittest
  import numpy
  import timeout_decorator
  from transformers import MBartConfig, is_flax_available
  from transformers.testing_utils import require_flax, require_sentencepiece, require_tokenizers, slow
  from transformers.utils import cached_property
  from ...generation.test_generation_flax_utils import FlaxGenerationTesterMixin
  from ...test_modeling_flax_common import FlaxModelTesterMixin, ids_tensor
label_desc: Use image node_id 6 for calling the MBartHeadTests obj's underlying member method code with example usage: obj.test_shift_tokens_right() without return types