Throttle Mac app CPU usage

import os
import sys
import time
import signal

if len(sys.argv) < 3:
    print("usage: throttle pid|name max_CPU_percent\ne.g throttle handbrake 25, limits handbrake to 25% CPU")
    sys.exit()

pid = sys.argv[1]
cpuPercent = int(sys.argv[2])

if not pid.isdigit():
    processIDs = os.popen('pgrep -i %s' %(pid)).read().rstrip("\n")
    processIDList = filter(None, processIDs.split("\n"))
    if len(processIDList) == 1:
        pid = processIDList[0]
    elif len(processIDList) > 1:
        print("Matched more than one process: %s" %(processIDList))
        sys.exit(0)
    else:
        print("No matching process found for: %s" %(pid))
        sys.exit(0)

pid = int(pid)

sleepTime = 0.1 * (1 - (cpuPercent / 100.0))
runTime = 0.1 * cpuPercent / 100.0

def interrupt_handler(sentSignal, frame):
    os.kill(pid, signal.SIGCONT)
    exit(0)

signal.signal(signal.SIGINT, interrupt_handler)

while True:
    os.kill(pid, signal.SIGSTOP)
    time.sleep(sleepTime)
    os.kill(pid, signal.SIGCONT)
    time.sleep(runTime)