In here, in addition shouldn't we test the actual result?
```
In [1]: from sympy.physics.wigner import racah

In [2]: racah(5.5,7.5,9.5,6.5,8,9)
Out[2]: 
       _____ 
-719⋅╲╱ 598  
─────────────
   1158924   

In [3]: racah(5.5,7.5,9.5,6.5,8,9, prec=4)
Out[3]: -0.01517
```
i.e. test within some eps etc.