code: def load_speakers(self):
      # load speakers
      if self.model_config.use_speaker_embedding is not None:
          self.tts_speakers = load_speaker_mapping(
              self.tts_config.tts_speakers_json
          )
          self.num_speakers = len(self.tts_speakers)
      else:
          self.num_speakers = 0
      # set external speaker embedding
      if self.tts_config.use_external_speaker_embedding_file:
          speaker_embedding = self.tts_speakers[
              list(self.tts_speakers.keys())[0]
          ]["embedding"]
          self.speaker_embedding_dim = len(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 3 for calling the Synthesizer obj's underlying member method code with example usage: obj.load_speakers() without return types