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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_event_types(self):
 """Update event types in event type box."""

        self.idx_evt_type.clear()
        self.idx_evt_type.setSelectionMode(QAbstractItemView.ExtendedSelection)
        event_types = sorted(self.parent.notes.annot.event_types,
                             key=str.lower)

        for ty in event_types:
            item = QListWidgetItem(ty)
            self.idx_evt_type.addItem(item)