python 3.x - How to ask password for sudo using pyqt? -

cmd = subprocess.run(["sudo", "ovs-vsctl", "list-br"], stdout=subprocess.pipe, universal_newlines=true) 

this error message gets shown when try run it.

sudo: no tty present , no askpass program specified 

this pyqt5 application trying out. want know how can ask administrator password in gui app?

this code:

#!/usr/bin/python3 # -*- coding: utf-8 -*-  import os, sys, design, subprocess pyqt5 import qtcore, qtgui, qtwidgets   class exampleapp(qtwidgets.qmainwindow, design.ui_mainwindow):     def __init__(self):         super(self.__class__, self).__init__()         self.setupui(self)         self.button1.clicked.connect(self.browse_folder)      def browse_folder(self):         self.listwidget.clear()          cmd = subprocess.run(["sudo", "ovs-vsctl", "list-br"], stdout=subprocess.pipe, universal_newlines=true)         bridges = cmd.stdout.split('\n')          if bridges:             bridge in bridges:                 self.listwidget.additem(bridge)  def main():     app = qtwidgets.qapplication(sys.argv)     form = exampleapp()     form.show()     app.exec_()  if __name__ == '__main__':     main()