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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 remove_action_callback(self, *event):
 """Callback method for remove action The method checks whether a shortcut ('Delete') is in the gui config model which shadow the delete functionality of maybe active a entry widget. If a entry widget is active the remove callback return with None. """

        if react_to_event(self.view, self.tree_view, event) and \
                not (self.active_entry_widget and not is_event_of_key_string(event, 'Delete')):
            self.on_remove(None)
            return True