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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):
 """Update the event types list, info, when dialog is opened."""

        self.filename = self.parent.notes.annot.xml_file
        
        self.event_types = self.parent.notes.annot.event_types
        self.idx_evt_type.clear()
        for ev in self.event_types:
            self.idx_evt_type.addItem(ev)