code: def forward(
      self, input: torch.Tensor, input_lengths: torch.Tensor
  ) -> Tuple[torch.Tensor, torch.Tensor]:
      raise NotImplementedError
  
file_path: espnet/espnet2/tts/feats_extract/abs_feats_extract.py
imports: from abc import ABC, abstractmethod
  from typing import Any, Dict, Tuple
  import torch
label_desc: Use image node_id 3 for calling the AbsFeatsExtract obj's underlying member method code with example usage: obj.forward(input, input_lengths) without return types