You replaced the default sys.path
list with a single path. Instead you can insert the new path:
PyObject *sys_path, *path;
sys_path = PySys_GetObject("path");
if (sys_path == NULL || !PyList_Check(sys_path)) {
/* ZOMG! That's so wrong... */
return;
}
path = PyString_FromString(path_to_PythonCode);
PyList_Insert(sys_path, 0, path);
Py_DECREF(path);