code: def unzoom(self, full=False, delay_draw=False):
          
          if full:
              self.zoom_lims = self.zoom_lims[:1]
              self.zoom_lims = []
          elif len(self.zoom_lims) > 0:
              self.zoom_lims.pop()
          self.set_viewlimits()
          if not delay_draw:
              self.canvas.draw()
docs: unzoom display 1 level or all the way