how to set timeout for os.popen

[Ho Yeung Lee]

while 1:
runner = os.popen("tracert -d www.hello.com")
o=runner.read()
print(o)
runner.close()
runner = os.popen("tracert -d www.hello.com")
o=runner.read()
print(o)
runner.close()
runner = os.popen("tracert -d www.hello.com")
o=runner.read()
print(o)
runner.close()


after running over 1 hour, it stop and not return in one of tracert

how to set timeout and know that this is timeout?