I  am trying to convert a .vtu mesh file to the .xml format. has anyone done this already? NekMesh Doesn't have this feature, I tried implementing it myself, but am having some challenges that I need to work out with how vtk access's each cell.

I am also gettting some errors like:

 Warning: degenerate tetrahedron, 3rd vertex is = 4.74539e-05 from face
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