With the backport of the Python 3 ssl module, the default context options of the ssl module were changed.

While this provides better security in many cases, it also causes breakage with servers or clients which do not support TLSv1 and later.

The ssl module should provide a way to globally set the default context options to work around this to allow e.g. removing the OP_NO_SSLv3 option in order to get things to work again without having to change the application using the ssl module.