How to timeout a statement

Question

how to time-out a statement/block of code in python?

I tried using the below looking at a post but it couldn't identify the signal:

wls:/offline> import signal

Traceback (innermost last):

  File "<console>", line 1, in ?

ImportError: no module named signal

code:

import os
import signal

def handler(signum, frame):
    print "Forever is over!"    
    raise Exception("end of time")

def loop_forever():
    import time
    while 1:
        print "sec"
        time.sleep(1)

signal.signal(signal.SIGALRM, handler)
signal.alarm(10)

try:
    loop_forever()
except Exception, exc:
    print exc

Answer 1

This seems to be working

Which calls a method after the timeout:

from threading import Timer

import time


def timeout():

    print 'in timeout'


def main():

    print 'it keeps going and going ',

    while 1:

        print 'and going '

        time.sleep(3)


try:

    Timer(5.0,timeout).start()

    main()

except:

    print "whoops"