code: def test_legacy_behaviour(self):
      self.tokenizer.legacy_behaviour = True
      inputs = self.tokenizer(
          "UN Chief says there is no military solution in Syria",
          src_lang="eng_Latn",
          tgt_lang="fra_Latn",
      )
      self.assertEqual(
          inputs.input_ids,
          [
              16297,
              134408,
              25653,
              6370,
              248,
              254,
              103929,
              94995,
              108,
              49486,
              2,
              256047,
          ],
      )
  
      self.tokenizer.legacy_behaviour = False
      inputs = self.tokenizer(
          "UN Chief says there is no military solution in Syria",
          src_lang="eng_Latn",
          tgt_lang="fra_Latn",
      )
      self.assertEqual(
          inputs.input_ids,
          [
              256047,
              16297,
              134408,
              25653,
              6370,
              248,
              254,
              103929,
              94995,
              108,
              49486,
              2,
          ],
      )
  
imports: import shutil
  import tempfile
  import unittest
  from transformers import SPIECE_UNDERLINE, AddedToken, BatchEncoding, NllbTokenizer, NllbTokenizerFast, is_torch_available
  from transformers.testing_utils import get_tests_dir, nested_simplify, require_sentencepiece, require_tokenizers, require_torch
  from ...test_tokenization_common import TokenizerTesterMixin
label_desc: Use image node_id 11 for calling the NllbDistilledIntegrationTest obj's underlying member method code with example usage: obj.test_legacy_behaviour() without return types