Hi,

I am using Pumas for Academia and I would like to do either

```
...
@pre
...
A = ... #some matrix composed of model parameters
b = ... #some vector composed of model parameters
x = A\b
...
```

or

```
...
@pre
...
A = ... #some matrix composed of model parameters
b = ... #some vector composed of model parameters
prob = LinearProblem(A, b)
x = solve(prob)
...
```

but both throw this stacktrace (quite long), which is I presume due to it trying to do both symbolically and some relevant operators not being defined. Is there a way to do this currently? Is there a way around the error?

Many thanks!