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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 update(self):
 """Once you open a dataset, it activates all the widgets. """

        self.info.display_dataset()
        self.overview.update()
        self.labels.update(labels=self.info.dataset.header['chan_name'])
        self.channels.update()

        try:
            self.info.markers = self.info.dataset.read_markers()
        except FileNotFoundError:
            lg.info('No notes/markers present in the header of the file')
        else:
            self.notes.update_dataset_marker()