code: def _grow(list_of_lists, num_new):
      
      first = list_of_lists[0]
      for i in range(num_new):
          list_of_lists.append(copy.deepcopy(first))
      return list_of_lists
docs: Given a list of lists, and a number of new lists to add, copy the
      content of the first list into the new ones, and add them to the list
      of lists.