> And don't get me started on the pain of trying to build an Ordered Dictionary with a default initial value!

  >>> from collections import defaultdict
  >>> from datetime import datetime
  >>>
  >>> d = defaultdict(datetime.now)
  >>> d[1], d[2], d[3], d[4], d[0]
  (datetime.datetime(2021, 7, 9, 15, 50, 52, 87605), datetime.datetime(2021, 7, 9, 15, 50, 52, 87613), datetime.datetime(2021, 7, 9, 15, 50, 52, 87614), datetime.datetime(2021, 7, 9, 15, 50, 52, 87615), datetime.datetime(2021, 7, 9, 15, 50, 52, 87616))
  >>> for k,v in d.items():
  ...   print(k,v)
  ...
  1 2021-07-09 15:50:52.087605
  2 2021-07-09 15:50:52.087613
  3 2021-07-09 15:50:52.087614
  4 2021-07-09 15:50:52.087615
  0 2021-07-09 15:50:52.087616
  >>>

Seems pretty good to me?