Opening a subwindow from a button event

Hello. I would like to ask how do i can open a subwindow from a button clicked event.

I learned from this tutorial that we can call our .ui files made on QtDesigner on a .py file and write only the events that we want to occour. However, i want to write a event from a clicked button that will call a second window, and would be great if this new subwindow would come from a different .ui file.

How do I do that?

I wrote an example for you:

import sys
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *

WINDOW_UI_FILE = "/home/user/window.ui"
DIALOG_UI_FILE = "/home/user/dialog.ui"

class Dialog(QDialog, dialog_form):

    def __init__(self, *args, **kwargs):
        super(QDialog, self).__init__(*args, **kwargs)        

class Window(QMainWindow, window_form):

    def __init__(self, *args, **kwargs):
        super(QMainWindow, self).__init__(*args, **kwargs)  

    def show_dialog(self):
        dialog = Dialog()

def main():

    app = QApplication(sys.argv)

    window_form, _ = uic.loadUiType(WINDOW_UI_FILE) 
    dialog_form, _ = uic.loadUiType(DIALOG_UI_FILE)

    window = Window()

If necessary, instead of a QDialog, it could be a QMainWindow.