docs: def valueAt(self, point):
          """
          Returns the value within the chart for the given point.
          
          :param      point | <QPoint>
          
          :return     {<str> axis name: <variant> value, ..}
          """
          chart_point = self.uiChartVIEW.mapFromParent(point)
          scene_point = self.uiChartVIEW.mapToScene(chart_point)
          return self.renderer().valueAt(self.axes(), scene_point)