lightning-qt without plugin

gui.py

#!/usr/bin/env python3
import os

from lightning import LightningRpc, Plugin, RpcError
from PyQt5.QtWidgets import QApplication, QWidget, QMainWindow

from mainWindow import MainWindow

def gui():
    """Launches the Qt GUI"""
    app = QApplication([])
    win = QMainWindow()
    win.show()
    return "Succesfully stopped lightning-qt" if not app.exec_() else "An error occured"

if __name__ == "__main__":
    gui()