def rename_eventtype(self, test_name=None, test_new_name=None):
        """action: create dialog to rename event type."""
        if test_name and test_new_name:
            name = test_name, True
            new_name = test_new_name, True
        else:
            name = QInputDialog.getText(self, 'Rename Event Type',
                                        'Enter name of event type to rename.')
        
        if name[1]:
            new_name = QInputDialog.getText(self, 'Rename Event Type',
                                            'Enter new name for event type.')
            
            if new_name[1]:
                self.annot.rename_event_type(name[0], new_name[0])
                self.display_eventtype()
                self.update_annotations()
action: create dialog to rename event type.