code: def test_blank_id(self):
      self.assertEqual(self.empty_vocab.blank_id, 0)
      self.assertEqual(self.base_vocab.blank_id, self.phonemes.blank_id)
  
file_path: TTS/tests/text_tests/test_characters.py
imports: import unittest
  from TTS.tts.utils.text.characters import BaseCharacters, BaseVocabulary, Graphemes, IPAPhonemes
label_desc: Use image node_id 3 for calling the BaseVocabularyTest obj's underlying member method code with example usage: obj.test_blank_id() without return types