Modules Contact and ModelManager

[arichel]

Dear Maintainer,

After installing PyFEM, I encountered some issues when running the examples in Chapter 02. Specifically, the module pyfem.io.InputReader attempts to import two classes that appear to be missing:

Contact from pyfem.fem.Contact
ModelManager from pyfem.models.ModelManager

Upon inspection, I noticed that a module and class named pyfem.models.Contact does exist, but the base class pyfem.models.BaseModel is missing, leading to import errors.

Could you advise if these classes are defined elsewhere or if there might be a different version where they are included?

Thank you for your assistance and for your great work on PyFEM!