Not clear if this is needed, but the code compiles.
This, however, does not solve the issue of relax thinking the C module is not compiled,
giving the following error message upon launching:
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ImportError: dlopen(/Users/semor/Documents/pse-4/collaborations/relax/relax-1.3_inversion-recovery/maths_fns/relax_fit.so, 2): Symbol not found: _curve_type
Referenced from: /Users/semor/Documents/pse-4/collaborations/relax/relax-1.3_inversion-recovery/maths_fns/relax_fit.so
Expected in: flat namespace
in /Users/semor/Documents/pse-4/collaborations/relax/relax-1.3_inversion-recovery/maths_fns/relax_fit.so
Relaxation curve fitting is unavailable, try compiling the C modules.
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