code: def call(
      self, characters, text_lengths=None, frames=None, training=None
  ):
      if training:
          return self.training(characters, text_lengths, frames)
      if not training:
          return self.inference(characters)
      raise RuntimeError(" [!] Set model training mode True or False")
  
file_path: TTS/TTS/tts/tf/models/tacotron2.py
imports: import tensorflow
  from tensorflow import keras
  from TTS.tts.tf.layers.tacotron2 import Encoder, Decoder, Postnet
  from TTS.tts.tf.utils.tf_utils import shape_list
label_desc: Use image node_id 2 for calling the Tacotron2 obj's underlying member method code with example usage: obj.call(characters, text_lengths, frames, training) and returns: self, self