Python start subprocess kill it after timeout and save log file

Question

I have following code which should run the binary and terminate after 5 second and log the stdout which generated by the binary.

But the below code not logging any data to log.txt.

with open("log.txt", "w") as output:
        try:
            process = subprocess.run(["./binary", "2000", "0"], stdout=output,timeout=5)
            if out.returncode != 0:
                return False

        except (subprocess.TimeoutExpired, UnicodeDecodeError) as e:
            return False