bright.py

#!/usr/bin/python3
# change brightness level on all monitors simultaneously on linux ubuntu

import os
import re
from sys import argv

try:
    brightness_level = float(argv[1])
except IndexError:
    brightness_level = 1.0

if brightness_level <= 0:
    brightness_level = 0.1

xrandr_lines = os.popen("xrandr").read()
outputs = re.findall(r'([\-\w]+) connected', xrandr_lines, re.M)
for output in outputs:
    os.popen("xrandr --output " + output + " --brightness " + str(brightness_level))