Help with Python 3.10, C-API and initialization

Python Help
1

I’m updating a package to work with Python 3.10. It is a package which loads python interpreter into another process via shared library. Everything works in 3.9 and earlier, but due to changes made in 3.10 existing code, which was calling Py_Main no longer properly works, i.e sys.prefix and sys.exec_prefix aren’t properly intialized when executed in the virtual environment.
So I went with the Python Initialization Configuration method.

When I just call Py_RunMain() instead of Py_Main() – everything works as expected, with the exception of parsing of command line arguments.
So I created an (what it seems to be an empty PyConfig object, into which I copied arguments using PyConfig_SetBytesArgv. But after doing that, I now no longer get correct sys.prefix and sys.exec_prefix inside of virtualenv.

My pseudo-C code looks as follows now:

int main(int argc, char **argv)
{
    PyStatus status;
    PyConfig config;

    Py_SetProgramName(...); 
    Py_Initialize();
    PyEval_InitThreads();
    PyEval_SaveThread();
    PyConfig_InitPythonConfig(&config);

    status = PyConfig_SetBytesArgv(&config, argc, argv);
    if (PyStatus_Exception(status)) {
        goto exception;
    }

    status = Py_InitializeFromConfig(&config);
    if (PyStatus_Exception(status)) {
        goto exception;
    }
    PyConfig_Clear(&config);

    return Py_RunMain();

exception:
    PyConfig_Clear(&config);
    if (PyStatus_IsExit(status)) {
        return status.exitcode;
    }
    Py_ExitStatusException(status);
}

What am I missing here?

Thanks!