code: def memorized_datetime(seconds):
      '''Create only one instance of each distinct datetime'''
      try:
          return _datetime_cache[seconds]
      except KeyError:
          # NB. We can't just do datetime.utcfromtimestamp(seconds) as this
          # fails with negative values under Windows (Bug #90096)
          dt = _epoch + timedelta(seconds=seconds)
          _datetime_cache[seconds] = dt
          return df memorized_datetime(seconds):
      '''Create only one instance of each distinct datetime'''
      try:
          return _datetime_cache[seconds]
      except KeyError:
          # NB. We can't just do datetime.utcfromtimestamp(seconds) as this
          # fails with negative values under Windows (Bug #90096)
          dt = _epoch + timedelta(seconds=seconds)
          _datetime_cache[seconds] = dt
          return dt
docs: Create only one instance of each distinct datetime