Help with variational problem for circuit flow analysis

General
1

I’m trying to use fenics to solve the attached equation, however I cannot figure out how to represent this in the code?

I defined the variational problem as such:

(u, p) = TrialFunctions(W)
(v, q) = TestFunctions(W)
a = inner(grad(u), grad(v)) * dx - p * div(v) * dx + div(u) * q * dx
L = inner(f, v) * dx

But it gives me an attribute error on this line:
(u, p) = TrialFunctions(W)

Any ideas?

formula 2

2

Please provide a minimal reproducible example using markdown formatting, ie.

```python
# ADd python code here
```

and make sure the example runs with copy-pasting it into an editor