QMessageBox и потоки

from PyQt5 import uic
from PyQt5.QtWidgets import *
import sys
import datetime as dt
import threading
 
 
def thread(my_func):
    def wrapper(*args, **kwargs):
        my_thread = threading.Thread(target=my_func, args=args, kwargs=kwargs)
        my_thread.start()
 
    return wrapper
 
 
StyleSheet = '''
    QLineEdit {
        border-width: 1px;
        border-style: solid;
        border-color: rgb(77, 77, 77);
    }
    QLineEdit:focus {
        border-color: rgb(89, 89, 89);
    }
    QPlainTextEdit {
        border-width: 1px;
        border-style: solid;
        border-color: rgb(77, 77, 77);
    }
    QPlainTextEdit:focus {
        border-color: rgb(89, 89, 89);
    }
'''
 
Form, Window = uic.loadUiType("pomny.ui")
app = QApplication([])
app.setStyleSheet(StyleSheet)
app.setStyle('Fusion')
window = Window()
window.setFixedSize(350, 540)
form = Form()
form.setupUi(window)
window.show()
 
 
@thread
def inf_baze(signal):
    if form.lineEdit.text() != '' and form.lineEdit_2.text() != '' and form.comboBox.currentText() != '' \
            and form.plainTextEdit.toPlainText() != '':
        comboBox1 = int(form.comboBox.currentText())
        lineEdit_hour = int(form.lineEdit.text())
        lineEdit_minutes = int(form.lineEdit_2.text())
        text_message = form.plainTextEdit.toPlainText()
        activate_button_time = dt.datetime.now()
        time_interval = activate_button_time + dt.timedelta(minutes=comboBox1)
        end_time = activate_button_time + dt.timedelta(hours=lineEdit_hour, minutes=lineEdit_minutes)
        while True:
            if dt.datetime.now() >= time_interval:
                msg = QMessageBox()
                msg.setText(text_message)
                msg.setWindowTitle("Message")
                msg.setStandardButtons(QMessageBox.Ok)
                msg = msg.exec_()
                time_interval += dt.timedelta(minutes=comboBox1)
            if dt.datetime.now() >= end_time:
                end_msg = QMessageBox()
                end_msg.setText("Работа приложения закончена")
                end_msg.setWindowTitle("End Message")
                end_msg.setStandardButtons(QMessageBox.Ok)
                end_msg = end_msg.exec_()
                break
            if form.pushButton_2.click() is True:
                end_msg2 = QMessageBox()
                end_msg2.setText("Работа приложения преждевременно закончена")
                end_msg2.setWindowTitle("End Message")
                end_msg2.setStandardButtons(QMessageBox.Ok)
                end_msg2 = end_msg2.exec_()
 
                break
    else:
        print("2")
 
 
form.comboBox.addItems(["30", "60", "90", "120"])
form.pushButton.clicked.connect(inf_baze)
 
sys.exit(app.exec())