code: def _set_voice_dirs(self, voice_dirs):
      def_voice_dir = None
      if isinstance(self.config.DEF_SPEAKER_DIR, str):
          os.makedirs(self.config.DEF_SPEAKER_DIR, exist_ok=True)
          if os.path.isdir(self.config.DEF_SPEAKER_DIR):
              def_voice_dir = self.config.DEF_SPEAKER_DIR
      _voice_dirs = [def_voice_dir] if def_voice_dir is not None else []
      if voice_dirs is not None:
          if isinstance(voice_dirs, str):
              voice_dirs = [voice_dirs]
          _voice_dirs = voice_dirs + _voice_dirs
      return _voice_dirs
  
imports: import os
  from dataclasses import dataclass
  from typing import Optional
  import numpy
  from coqpit import Coqpit
  from encodec import EncodecModel
  from transformers import BertTokenizer
  from TTS.tts.layers.bark.inference_funcs import codec_decode, generate_coarse, generate_fine, generate_text_semantic, generate_voice, load_voice
  from TTS.tts.layers.bark.load_model import load_model
  from TTS.tts.layers.bark.model import GPT
  from TTS.tts.layers.bark.model_fine import FineGPT
  from TTS.tts.models.base_tts import BaseTTS
label_desc: Use image node_id 9 for calling the Bark obj's underlying member method code with example usage: obj._set_voice_dirs(voice_dirs) and returns: _voice_dirs