Password and username
Can you use arrays to make a program to be used as a username and password checker
Python dictionaries are the way to go. Also, if you are learning python, I recommend learning python 3, because python 2 is supposedly going to be eventually deprecated.
https://www.tutorialspoint.com/python/python_dictionary.htm, or any tutorial on python dictionaries are a must-read for this type of project (not really, but you get my point)