Changes

:* Time object code : from '''Think Python''' by Allen B. Downey: [http://greenteapress.com/thinkpython2/html/thinkpython2017.html Chapter 16] and [http://greenteapress.com/thinkpython2/html/thinkpython2018.html Chapter 17]:* Date Data object : [https://docs.python.org/3/reference/datamodel.html#special-method-names special method name]