python wrappings for vtkSelectioNode. The methods SetFieldType and SetContentType don't update values
vtk 9.3 installed from pip
selection_node = vtkSelectionNode()
selection_node.SetFieldType(vtkSelectionNode.INDICES)
selection_node.SetContentType(vtkSelectionNode.POINT)
However, the following works:
selection_node = vtkSelectionNode()
selection_node.GetProperties().Set(vtkSelectionNode.CONTENT_TYPE(), vtkSelectionNode.INDICES)
selection_node.GetProperties().Set(vtkSelectionNode.FIELD_TYPE(), vtkSelectionNode.POINT)