import sys from PyQt5.QtGui import QPainter from PyQt5.QtWidgets import QApplication, QMainWindow from BubbleWidget import BubbleWidget def main(): app = QApplication(sys.argv) main_window = QMainWindow() main_window.resize(1024, 800) bubble_widget = BubbleWidget() main_window.setCentralWidget(bubble_widget) main_window.show() sys.exit(app.exec_()) if __name__ == "__main__": main()