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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 _mouse_handler(self, cli, mouse_event):
 """ Mouse handler. Called when the UI control doesn't handle this particular event. """

        if mouse_event.event_type == MouseEventType.SCROLL_DOWN:
            self._scroll_down(cli)
        elif mouse_event.event_type == MouseEventType.SCROLL_UP:
            self._scroll_up(cli)