import RPi.GPIO as GPIO
import time

GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)
# Define output pins and set them low
lasers = [18, 23, 24, 25]
for x in lasers:
    GPIO.setup(x, GPIO.OUT)
    GPIO.output(x, GPIO.LOW)

for i in range(1, 6):
    time.sleep(5)
    for x in lasers:
        GPIO.output(x, GPIO.HIGH)
    time.sleep(5)
    for x in lasers:
        GPIO.output(x, GPIO.LOW)