CalculiX is a free and open-source finite-element analysis application that uses an input format similar to Abaqus.

[3] The pre-processor component of CalculiX can generate grid data for the computational fluid dynamics programs duns, ISAAC and OpenFOAM.

It can also generate input data for the commercial FEM programs Nastran, Ansys and Abaqus.

The library provides Python access to building, loading, meshing, solving, and querying CalculiX results for 2D models.

There is a lot good examples of use of CalculiX[11] by Prof. Martin Kraska, Brandenburg University of Applied Sciences.