pyxll crashes with abort messages

Question

I am trying to integrate a python function in Excel using pyxll add-in. To do that, I have installed pyxll and configured it as the following:

pyxll.cfg

[PYTHON]
pythonhome = ./venv/Scripts
executable = ./venv/Scripts/pythonw.exe

pythonpath =
    ./venv/Lib/site-packages/my_library/module1
    ./venv/Lib/site-packages/my_library/module2

[PYXLL]
modules =
    module1
    module2

ribbon =
    ./venv/Lib/site-packages/my_library/ribbon.xml

error_handler = pyxll.error_handler
developer_mode = 1

and module1 is implemented as the following:

module1

@xl_func('int ,int :int')
def test_function(number1, number2) -> int:
    return number1 + number2

module1

@xl_func('int ,int :int')
def test_function2(number1, number2) -> int:
    return number1 * number2

however when i run Excel, it crashes with the following error message (repeating dozens of times):

2023-09-14 13:11:26,291 - ERROR : C runtime 'abort()' has been called.

Any idea what might be the cause?