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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_chan_labels(self):
 """Create the channel labels, but don't plot them yet. Notes ----- It's necessary to have the width of the labels, so that we can adjust the main scene. """

        self.idx_label = []
        for one_grp in self.parent.channels.groups:
            for one_label in one_grp['chan_to_plot']:
                item = QGraphicsSimpleTextItem(one_label)
                item.setBrush(QBrush(QColor(one_grp['color'])))
                item.setFlag(QGraphicsItem.ItemIgnoresTransformations)
                self.idx_label.append(item)