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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 on_hazard_exposure_bookmark_toggled(self, enabled):
 """Update the UI when the user toggles the bookmarks radiobutton. :param enabled: The status of the radiobutton. :type enabled: bool """

        if enabled:
            self.bookmarks_index_changed()
        else:
            self.ok_button.setEnabled(True)
        self._populate_coordinates()