Tkinter
Tkinter
Tkinter is a module in Python that stands for Tk-interaction. This somewhat exotic acronym is derived from the fact that Tkinter's main purpose in Python is to interact with a GUI system dubbed Tk. Because you could alternately just use Tk,
Downloading Tkinter
Tkinter is already downloaded when you install Python. To test Tkinter, do
import tkinter
tkinter._test()
Learn More about Tkinter
If you want to learn more about tkinter, you can take AoPS's online course Intermediate Programming with Python at https://artofproblemsolving.com/school/course/python2.