Rpi 1Hz PWM

import RPi.GPIO as GPIO
import time
GPIO.setmode(GPIO.BCM)
GPIO.setup(5,GPIO.OUT)
GPIO.setup(13,GPIO.IN,pull_up_down=GPIO.PUD_UP)
p=GPIO.PWM(5,1)
p.start(50)
input('Press return to stop')
p.stop()
GPIO.cleanup()