code: def concat_lists(list_a: List[List[Any]], list_b: List[List[Any]]):
      list_u = []
      for element_a, element_b in zip(list_a, list_b):
          list_u.append(element_a + element_b)
      return list_u
  
imports: from typing import Any, List
  import nltk
  from deeppavlov.core.common.registry import register
label_desc: Use image node_id 1 for calling a global function with example usage: concat_lists(list_a, list_b) and returns: list_u