But the datatype for date-time objects is namespaced as datetime.datetime. If you just enter import datetime into a Python program, you’re only importing the datetime library.

Each key is associated with a value, which can be any Python object. You use a key to obtain its related values, and the lookup time for each key/value pair is highly constant.

If you want to do time-of-day arthithmetic, the easiest thing to do is start with a datetime.datetime object with dummy values of year, month, and day, and add datetime.timedelta objects to it: ...