code: def init_speaker(self, speaker_idx):
      # load speakers
      speaker_embedding = None
      if hasattr(self, "tts_speakers") and speaker_idx is not None:
          assert speaker_idx < len(
              self.tts_speakers
          ), f" [!] speaker_idx is out of the range. {speaker_idx} vs {len(self.tts_speakers)}"
          if self.tts_config.use_external_speaker_embedding_file:
              speaker_embedding = self.tts_speakers[speaker_idx][
                  "embedding"
              ]
      return speaker_embedding
  
imports: import time
  import numpy
  import torch
  import pysbd
  from TTS.utils.audio import AudioProcessor
  from TTS.utils.io import load_config
  from TTS.tts.utils.generic_utils import setup_model
  from TTS.tts.utils.speakers import load_speaker_mapping
  from TTS.vocoder.utils.generic_utils import setup_generator, interpolate_vocoder_input
  from TTS.tts.utils.synthesis import *
  from TTS.tts.utils.text import make_symbols, phonemes, symbols
label_desc: Use image node_id 4 for calling the Synthesizer obj's underlying member method code with example usage: obj.init_speaker(speaker_idx) and returns: speaker_embedding