code: def attn_mask_postprocess(attn_mask):
      # [b, 1, s, s]
      # Attn_masks for enc-dec attn and dec attn is None when trying to get just the encoder hidden states.
      if attn_mask is None:
          return None
      extended_attention_mask = attn_mask.unsqueeze(1)
      return extended_attention_mask
  
imports: import itertools
  import math
  from typing import Dict, Iterator, List, Tuple, Union
  import torch
  import torch.nn
  from torch import Tensor
label_desc: Use image node_id 14 for calling a global function with example usage: attn_mask_postprocess(attn_mask) and returns: extended_attention_mask, None