TypeError NoneType when importing PySide6 background worker, but working when merged into main script about nuitka HOT 6 CLOSED

import sys
from PySide6.QtWidgets import QApplication, QMainWindow, QPushButton, QVBoxLayout, QWidget, QTextEdit
from PySide6.QtCore import Slot
from src.pyside.Worker import WorkerThread


class MainWindow(QMainWindow):
    def __init__(self):
        super().__init__()
        self.init_ui()

    def init_ui(self):
        self.setWindowTitle('PySide6 Background Task Example')
        self.setGeometry(100, 100, 400, 300)

        # Main layout
        layout = QVBoxLayout()

        # Text area to display results
        self.text_area = QTextEdit()
        self.text_area.setReadOnly(True)
        layout.addWidget(self.text_area)

        # Button to start the background task
        self.start_button = QPushButton('Start Task')
        self.start_button.clicked.connect(self.start_task)
        layout.addWidget(self.start_button)

        # Set the central widget
        central_widget = QWidget()
        central_widget.setLayout(layout)
        self.setCentralWidget(central_widget)

    def start_task(self):
        # Disable the button to prevent multiple clicks
        self.start_button.setEnabled(False)
        self.text_area.append("Task started...")

        # Create and start the worker thread with a custom function and arguments
        self.worker_thread = WorkerThread(self.long_running_task, 5)
        self.worker_thread.result_signal.connect(self.task_finished)
        self.worker_thread.start()

    @Slot(str)
    def task_finished(self, result):
        # Enable the button again and display the result
        self.start_button.setEnabled(True)
        self.text_area.append(result)

    def long_running_task(self, seconds):
        import time
        time.sleep(seconds)  # Simulate a long-running task
        return f"Task completed after {seconds} seconds!"


if __name__ == '__main__':
    app = QApplication(sys.argv)
    main_window = MainWindow()
    main_window.show()
    sys.exit(app.exec())