code: def truncate_tokens(
      batch: List[List[str]], max_seq_len: int, pad_token: str
  ) -> List[List[str]]:
      truncated: List[List[str]] = []
      for sentence in batch:
          if len(sentence) == 0:
              truncated.append([pad_token])
          elif max_seq_len > 0:
              truncated.append(sentence[0:max_seq_len])
          else:
              truncated.append(sentence)
      return truncated
  
imports: from typing import List, NamedTuple, Optional, Tuple
  import torch
  from torch import Tensor
label_desc: Use image node_id 9 for calling a global function with example usage: truncate_tokens(batch, max_seq_len, pad_token) and returns: truncated