Method _switch_on_zoom_mode

lib/matplotlib/backend_tools.py:758–760

(self, event)

        self._zoom_mode = event.key

    def _switch_on_zoom_mode(self, event):
        self._zoom_mode = event.key
        self._mouse_move(event)

    def _switch_off_zoom_mode(self, event):
        self._zoom_mode = None