Problème lecture fichier en python

from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
from .apr import Ui_Form
import os
class appr(QWidget, Ui_Form):
	def __init__(self, parent=None):
		super(appr, self).__init__(parent)
		self.setupUi(self)

		self.center()
		self.traitement()
		self.action()
	def traitement(self):
		self.textLicence.setVisible(False)
		self.text = open("Licence.txt","r")
		self.text.read()
		self.textLicence.setPlainText(self.text)
	def action(self):
		self.licence.clicked.connect(self.showLicence)
	def showLicence(self):
		self.textLicence.setVisible(True)
		self.lab3.setVisible(False)
	def center(self):
		qr = self.frameGeometry()
		cp = QDesktopWidget().availableGeometry().center()
		qr.moveCenter(cp)
		self.move(qr.topLeft())

self.text = open("~/Dektop/Projet/Class/Licence.txt","r")