As described in Issue9517, many test modules do not make use of the helpers in script_helpers.py to invoke the python interpreter in a subprocess. Issue9517 will be broken down into several smaller issues so we can address smaller change sets. This issue is to update _test_multiprocessing.py to use script_helpers.py.
Updated both tests in _test_mulitprocessing.py which were using sys.exectuable and Popen to use script_helpers instead, refactored script_helpers a bit to make this work.
Sorry but these patches have been lost in the huge database of open bugs and we forgot it. They have been written 3 years ago. Since that, Python moved to GitHub. If you are still interested to convert tests to script_helper, please open GitHub pull requests. I would suggest to start with a small one, and then see if other tests should be converted. I close the issue. Reopen it if you want to work again on it.