code: def flatten(list_of_lists):
      """
      Given a list of lists, flatten all the items into one list.
  
      :param list_of_lists:
      :return:
  
      >>> flatten([ [1, 2, 3], [4, 5, 6]])
      [1, 2, 3, 4, 5, 6]
      """
      return [val for sublist in list_of_lists for val in sublist]
  
imports: import re
  import sys
  import unicodedata
  from typing import Dict, List, Tuple
label_desc: Use image node_id 6 for calling a global function with example usage: flatten(list_of_lists) and returns: unknown