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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def cell_scalar(mesh, name):
 """ Returns cell scalars of a vtk object """

    vtkarr = mesh.GetCellData().GetArray(name)
    if vtkarr:
        if isinstance(vtkarr, vtk.vtkBitArray):
            vtkarr = vtk_bit_array_to_char(vtkarr)
        return vtk_to_numpy(vtkarr)