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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 display_window(self):
 """Read the channel name from QComboBox and plot its spectrum. This function is necessary it reads the data and it sends it to self.display. When the user selects a smaller chunk of data from the visible traces, then we don't need to call this function. """

        if self.idx_chan.count() == 0:
            self.update()

        chan_name = self.idx_chan.currentText()
        lg.debug('Power spectrum for channel ' + chan_name)

        if chan_name:
            trial = 0
            data = self.parent.traces.data(trial=trial, chan=chan_name)
            self.display(data)
        else:
            self.scene.clear()