class_docstr: Base Vocabulary class.
  
  This class only needs a vocabulary dictionary without specifying the characters.
  
  Args:
      vocab (Dict): A dictionary of characters and their corresponding indices.
docstr: Return number of tokens in the vocabulary.
docstr_tok: ["Return","number","of","tokens","in","the","vocabulary","."]
code: def num_chars(self):
      """Return number of tokens in the vocabulary."""
      return len(self._vocab)
  
imports: from dataclasses import replace
  from typing import Dict
  from TTS.tts.configs.shared_configs import CharactersConfig
label_desc: Use image node_id 10 for calling the BaseVocabulary obj's underlying member method code with example usage: obj.num_chars() and returns: len