Restart Maya from within Maya using Python script

maya_restart.py

import subprocess
import sys
import os
from maya import cmds

current_file = cmds.file(query=True, sceneName=True)
args = [sys.executable]
if current_file and os.path.exists(current_file):
    args.append("-file")
    args.append(current_file)

subprocess.Popen(args)

# Set abort to False if you want to save your current Maya preferences/hotkeys/colors
# Force ignores to prompt for file save (if you'd like to prompt for save, you should do that before starting the subprocess!)
cmds.quit(force=True, abort=True)