There's another group of built-in types that deal with
date and time representation. These types are part of the cal module and they are all timezone-unaware: local_datetime, local_date, local_time. They
represent values that could be displayed on a wall clock
or calendar without needing any specific time-zone
information. Alarms, holiday dates, or even regular
business hours could naturally be represented by these
types. Consider things like "Pi Day" or "alarm at 8:30 AM":
