I am trying to compute the tangent vectors at each vertex of an STL file. Using proper macros as declared in vtkPolyDataTangents “https://vtk.org/doc/nightly/html/vtkPolyDataTangents_8h_source.html”. The output data is “none”. I am using VTK ver 9.0 and python. Is there a way to retrieve the tangent vectors at each vertex?