code: def setUpClass(cls):
      cls.base_opts = {
          "seed": 3431,
          "share_vocab": False,
          "src_subword_model": "data/sample.bpe",
          "tgt_subword_model": "data/sample.bpe",
          "src_subword_nbest": 1,
          "tgt_subword_nbest": 1,
          "src_subword_alpha": 0.0,
          "tgt_subword_alpha": 0.0,
          "src_subword_vocab": "",
          "tgt_subword_vocab": "",
          "src_vocab_threshold": 0,
          "tgt_vocab_threshold": 0,
      }
  
imports: import unittest
  import copy
  import yaml
  import math
  from argparse import Namespace
  from onmt.transforms import get_transforms_cls, get_specials, make_transforms, TransformPipe
  from onmt.transforms.bart import BARTNoising
label_desc: Use image node_id 1 for calling the TestSubwordTransform obj's underlying member method code with example usage: obj.setUpClass(cls) without return types