How do I create an input box with Python?

You could try the Tkinter module:

from tkinter import *

master = Tk()
e = Entry(master)
e.pack()

e.focus_set()

def callback():
    print e.get() # This is the text you may want to use later

b = Button(master, text = "OK", width = 10, command = callback)
b.pack()

mainloop()

Result:

Of course, you may want to read a Tkinter tutorial.