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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def create_video(self):
 """Create video widget."""


        self.instance = vlc.Instance()

        video_widget = QFrame()
        self.mediaplayer = self.instance.media_player_new()
        if system() == 'Linux':
            self.mediaplayer.set_xwindow(video_widget.winId())
        elif system() == 'Windows':
            self.mediaplayer.set_hwnd(video_widget.winId())
        elif system() == 'darwin':  # to test
            self.mediaplayer.set_nsobject(video_widget.winId())
        else:
            lg.warning('unsupported system for video widget')
            return

        self.medialistplayer = vlc.MediaListPlayer()
        self.medialistplayer.set_media_player(self.mediaplayer)
        event_manager = self.medialistplayer.event_manager()
        event_manager.event_attach(vlc.EventType.MediaListPlayerNextItemSet,
                                   self.next_video)

        self.idx_button = QPushButton()
        self.idx_button.setText('Start')
        self.idx_button.clicked.connect(self.start_stop_video)

        layout = QVBoxLayout()
        layout.addWidget(video_widget)
        layout.addWidget(self.idx_button)
        self.setLayout(layout)