code: def __getitem__(self, index: int) -> SpeechToTextJointDatasetItem:
      s2t_dataset_item = super().__getitem__(index)
      src_tokens = None
      src_lang_tag = None
      if self.src_texts is not None and self.src_dict is not None:
          src_tokens = self.get_tokenized_src_text(index)
          src_tokens = self.src_dict.encode_line(
              src_tokens, add_if_not_exist=False, append_eos=True
          ).long()
          if self.use_src_lang_id > 0:
              src_lang_tag = self.get_lang_tag_idx(
                  self.src_langs[index], self.src_dict
              )
      tgt_lang_tag = None
      if self.cfg.prepend_tgt_lang_tag_no_change:
          # prepend_tgt_lang_tag_no_change: modify prev_output_tokens instead
          tgt_lang_tag = self.get_lang_tag_idx(
              self.tgt_langs[index], self.tgt_dict
          )
      ali = None
      if self.alignment is not None:
          ali = torch.Tensor(self.alignment[index]).float()
  
      return SpeechToTextJointDatasetItem(
          index=index,
          source=s2t_dataset_item.source,
          target=s2t_dataset_item.target,
          src_txt_tokens=src_tokens,
          tgt_lang_tag=tgt_lang_tag,
          src_lang_tag=src_lang_tag,
          tgt_alignment=ali,
      )
  
imports: import logging
  from pathlib import Path
  from typing import Dict, List, NamedTuple, Optional
  import torch
  from fairseq.data import ConcatDataset, Dictionary, ResamplingDataset
  from fairseq.data import data_utils
  from fairseq.data.audio.speech_to_text_dataset import S2TDataConfig, SpeechToTextDataset, SpeechToTextDatasetCreator
label_desc: Use image node_id 3 for calling the SpeechToTextJointDataset obj's underlying member method code with example usage: obj.__getitem__(index) and returns: SpeechToTextJointDatasetItem