How use python to get the ID of a selected point?

Currently I can use SelectSurfacePoints to highlight a point. So how do I get the ID or the coordinates of this point?
I found that Edit-Find Data can get information about the select point, but I don’t know how to do that in Python, because it doesn’t seem to be able to trace this operation.
Hope to get the help of experts here!
Thank you!

I use the following method to get the coordinates of the selected point, but the ID is 0, which is different from the original ID of the point, as if because of the filter:

        extractSelection = simple.ExtractSelection(Input = self.source)
        selectionData = paraview.servermanager.Fetch(extractSelection)
        cellIds = vtk.vtkIdList()
        selectionData.GetCellPoints(0, cellIds)
        for i in range(0, cellIds.GetNumberOfIds()):
            coord = selectionData.GetPoint(cellIds.GetId(i))

Is there any way to get the ID of this point in the original model?