Do Something While User Input Not Received

In Python, in what way can I do something on loop while user has not given an input. I have python client and I ask for user input, but while user has not given an input I'd like

Solution 1:

Maybe this can get you started:

from threading import Thread
from time import sleep

result = None

def update_every_second():
    while result is None:
        sleep(1)
        print "update"

t = Thread(target=update_every_second)
t.start()
result = raw_input('? ')

print "The user typed", result