i3wm empty workspaces

#!/usr/bin/python

import json
import subprocess
import time


def i3_msg(args):
    return json.loads(subprocess.check_output(["i3-msg"] + args))


def main():
    outputs = i3_msg(["-t", "get_outputs"])
    spaces = i3_msg(["-t", "get_workspaces"])
    next_space = max([space['num'] for space in spaces])
    for output in outputs:
        if output['active']:
            next_space += 1
            i3_msg(["workspace", str(output['current_workspace'])])
            i3_msg(["workspace", str(next_space)])


if __name__ == '__main__':
    main()