I recently had to get the current date (could be quite easily expanded to time also I believe) and found a solution I thought I would post incase someone has this problem.
It means you don't have to use a webservice like this tutorial suggests: http://zone.ni.com/reference/en-XX/help/373286A-01
The trick is using pythons datetime class. I find a lot of cool basic functions can be used this way. Here is the code that is run when the stop button is pressed:
from datetime import date