asfg.py

#!/usr/bin/env python3

import os;
import subprocess;
import sys;

if os.getuid() != 0:
    sys.exit('Error: must be run as root')

if len(sys.argv) < 2:
    sys.exit('Error: no command specified')

user_name = subprocess.check_output(
        "who | awk -v vt=tty$(fgconsole) '$0 ~ vt {print $1}'",
        shell=True
).decode('utf-8').rstrip('\n')

display_name = subprocess.check_output(
        "who | awk -v vt=tty$(fgconsole) '$0 ~ vt {print $5}'",
        shell=True
).decode('utf-8').rstrip('\n').lstrip('(').rstrip(')')

args = [
    "sudo",
    "-u", user_name,
    "DISPLAY=" + display_name,
    "--"
]

for arg in sys.argv[1:]:
    args.append(arg)

os._exit(subprocess.call(args))