Listing 3. Making a Copy of the Environment

// Get a reference to the main module.
PyObject* main_module =
   PyImport_AddModule("__main__");

// Get the main module's dictionary
// and make a copy of it.
PyObject* main_dict =
   PyModule_GetDict(main_module);
PyObject* main_dict_copy =
   PyDict_Copy(main_dict);

// Execute two different files of
// Python code in separate environments
FILE* file_1 = fopen("file1.py", "r");
PyRun_File(file_1, "file1.py",
           Py_file_input,
           main_dict, main_dict);

FILE* file_2 = fopen("file2.py", "r");
PyRun_File(file_2, "file2.py",
           Py_file_input,
           main_dict_copy, main_dict_copy);