It seems to be enabled by default since 2013/Python 3.4: https://bugs.python.org/issue5845 https://bugs.python.org/issue5845 https://github.com/python/cpython

It seems to be enabled by default since 2013/Python 3.4: https://bugs.python.org/issue5845 https://bugs.python.org/issue5845 https://github.com/python/cpython/commit/1a6cb30a346ba8812d6abc77fddee636ae06ccff https://github.com/python/cpython/commit/1a6cb30a346ba8812d6... https://docs.python.org/3.4/whatsnew/3.4.html#sys https://docs.python.org/3.4/whatsnew/3.4.html#sys Support already existed in Python 2, so it's sad that it took so long for it to be enabled by default.