Build tests for model extraction and utils

[suhacker1]

Is your feature request related to a problem? Please describe.
No tests exist for the different model extraction interfaces and for the utilities.

Describe the solution you'd like.
Create unit tests using Pytest and/or Hypothesis.

Describe alternatives you've considered.
N/A

Detail any additional context.
Either traditional unit testing or property-based testing is appropriate as long as the decision is justified. Make sure to add any new libraries to Poetry.

[suhacker1]

Build tests for model extraction