python3: How to Run Different Modules According to User Input?

I want to create a personal assistant in python3, and i want to make modules run according to user input.

Eg: like in this python2 project rahulxxarora/Jango (https://github.com/rahulxxarora/Jango)

*Time, date and day*

->What time is it jango? ->Can you tell me the date please. ->Whats the day today?

So any easy way to do this?