Function initPython

src/EnergyPlus/PythonEngine.cc:227–317

    }

    void initPython(EnergyPlusData &state, fs::path const &pathToPythonPackages)
    {
        PyStatus status;

        // first pre-config Python so that it can speak UTF-8
        PyPreConfig preConfig;
        // This is the other related line that caused Decent CI to start having trouble.  I'm putting it back to
        // PyPreConfig_InitPythonConfig, even though I think it should be isolated.  Will deal with this after IO freeze.
        PyPreConfig_InitPythonConfig(&preConfig);
        // PyPreConfig_InitIsolatedConfig(&preConfig);
        preConfig.utf8_mode = 1;
        status = Py_PreInitialize(&preConfig);
        if (PyStatus_Exception(status) != 0) {
            ShowFatalError(state, EnergyPlus::format("Could not pre-initialize Python to speak UTF-8... {}", status));
        }

        PyConfig config;
        PyConfig_InitIsolatedConfig(&config);
        config.isolated = 1;

        status = PyConfig_SetBytesString(&config, &config.program_name, PluginManagement::programName);
        if (PyStatus_Exception(status) != 0) {
            ShowFatalError(state, EnergyPlus::format("Could not initialize program_name on PyConfig... {}", status));
        }

        status = PyConfig_Read(&config);
        if (PyStatus_Exception(status) != 0) {
            ShowFatalError(state, EnergyPlus::format("Could not read back the PyConfig... {}", status));
        }

        if constexpr (std::is_same_v<typename fs::path::value_type, wchar_t>) {
            // PyConfig_SetString copies the wide character string str into *config_str.
            std::wstring const ws = pathToPythonPackages.generic_wstring();
            const wchar_t *wcharPath = ws.c_str();

            status = PyConfig_SetString(&config, &config.home, wcharPath);
            if (PyStatus_Exception(status) != 0) {
                ShowFatalError(state,
                               EnergyPlus::format("Could not set home to {} on PyConfig... {}", pathToPythonPackages.generic_string(), status));
            }
            status = PyConfig_SetString(&config, &config.base_prefix, wcharPath);
            if (PyStatus_Exception(status) != 0) {
                ShowFatalError(
                    state, EnergyPlus::format("Could not set base_prefix to {} on PyConfig... {}", pathToPythonPackages.generic_string(), status));
            }
            config.module_search_paths_set = 1;
            status = PyWideStringList_Append(&config.module_search_paths, wcharPath);
            if (PyStatus_Exception(status) != 0) {
                ShowFatalError(
                    state,
                    EnergyPlus::format("Could not add {} to module_search_paths on PyConfig... {}", pathToPythonPackages.generic_string(), status));
            }

        } else {
            // PyConfig_SetBytesString takes a `const char * str` and decodes str using Py_DecodeLocale() and set the result into *config_str
            // But we want to avoid doing it three times, so we PyDecodeLocale manually
            // Py_DecodeLocale can be called because Python has been PreInitialized.
            wchar_t *wcharPath = Py_DecodeLocale(pathToPythonPackages.generic_string().c_str(), nullptr); // This allocates!