openoffice calc macro : Copy a chart to GDI meta format by python macro

def myAddChart(oDataRangeAddress, oSheet, oChartPositionCell):        
        tmpChartName = "tmpChartName"
        #--------- make a chart
        oCharts = oSheet.Charts
                
        X = oChartPositionCell.Position.X
        Y = oChartPositionCell.Position.Y
                
        oCharts.addNewByName(tmpChartName, makeRectangle( X, Y, 8000, 3500 ), Array( oDataRangeAddress ), True, True)
        oChart = oCharts.getByName(tmpChartName)
        
        #==========================================================
        #--------- Copy the Chart to GDI meta image into the position on where the chart is
        #==========================================================
        oDoc = getReady()
        oController = oDoc.getCurrentController()

        oDrawPage = oSheet.getDrawPage() 
        nNumShapes = oDrawPage.getCount() 
        
        ### select the chart. 
        ### No way for direct selecting a chart. So, get shapes and find the chart from shapes.
        for loopi in range(nNumShapes) :
                oShape = oDrawPage.getByIndex( loopi ) 
                if "CLSID" in dir(oShape) : # only charts have the CLSID attribute
                        if oShape.CLSID == "12DCAE26-281F-416F-a234-c3086127382e"  : # this is the CLSID of charts
                                oController.select( oShape ) 
                                break
                                
        # PropertyValue format=3 means the PasteSpecial format to be the GDI meta file format
        PropertyValue = uno.createUnoStruct("com.sun.star.beans.PropertyValue")
        PropertyValue.Name = "Format"
        PropertyValue.Value = 3
        
        serviceMgr = uno.getComponentContext().ServiceManager
        dp = serviceMgr.createInstance('com.sun.star.frame.DispatchHelper')
        #--- copy the selected object (chart)
        dp.executeDispatch( oController.getFrame(), ".uno:Copy", "", 0, ())
        #--- remove the selected object
        oCharts.removeByName(tmpChartName)
        #--- now select the cell where the GDI meta image will be on
        oController.select(oChartPositionCell)
        #--- paste
        dp.executeDispatch( oController.getFrame(), ".uno:PasteSpecial", "", 0, (PropertyValue,))   # <- The last (PropertyValue,) option is important.
                

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