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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(self):
 """Create empty scene for power spectrum."""

        self.idx_chan = QComboBox()
        self.idx_chan.activated.connect(self.display_window)

        self.idx_fig = QGraphicsView(self)
        self.idx_fig.scale(1, -1)

        layout = QVBoxLayout()
        layout.addWidget(self.idx_chan)
        layout.addWidget(self.idx_fig)
        self.setLayout(layout)

        self.resizeEvent(None)