class_docstr: Base class for all S2ST auxiliary attention modules.
  Refer to https://arxiv.org/abs/2107.08661
code: def forward(
      self,
  ) -> torch.Tensor:
      # the return tensor should be shape of (batch)
      raise NotImplementedError
  
imports: from abc import ABC, abstractmethod
  import torch
label_desc: Use image node_id 2 for calling the AbsS2STAuxAttention obj's underlying member method code with example usage: obj.forward() without return types