SSLSocket.get_verified_chain() and get_unverified_chain() raise AttributeError after the TLS layer is torn down

Bug report

SSLSocket.get_verified_chain() and SSLSocket.get_unverified_chain() raise
AttributeError when called after the socket's TLS layer is torn down (for
example after unwrap()), while every other query method (cipher(),
version(), group(), ...) returns a value:

>>> s.unwrap()
>>> s.get_verified_chain()
Traceback (most recent call last):
  ...
AttributeError: 'NoneType' object has no attribute 'get_verified_chain'

The two methods access self._sslobj without the _checkClosed() /
if self._sslobj is None guard the sibling methods use. They were added in
gh-109113 (3.13), so 3.13 and later are affected.

CPython versions tested on:

3.16 (main)

Operating systems tested on:

Linux, macOS

Linked PRs

• gh-155328

Commencez par SSLSocket.get_verified_chain() et get_unverified_chain(), puis comparez leur gestion de self._sslobj avec celle des méthodes de requête correspondantes après unwrap(). Le travail est terminé lorsque les deux méthodes ne lèvent plus AttributeError lorsque la couche TLS est supprimée et que leur comportement correspond à celui des autres méthodes de requête dans cet état.