Changes

* Please use python's docstring to document your new python script (script level documentation) class, class functions and each of the external functions (function level documentation) you created for this assignment. The docstring should describe 'what' the class is for, what does each class function doesdo, not 'how' it doeswhat each data attribute is for.* The following shows the docstring that was added to the after() function which provides the following information when called with help(after) in the python interactive shell: