`http.client.HTTPSConnection._tunnel` returning None: string (as how it has been) or null (proper None)?

In this issue, in Python 3.14 and 3.15, an AttributeError can be raised when an invalid value (such as None) is passed and is not handled properly. As a solution, it could be handled differently depending on the desired outcome: Converting None to the string "None": keeps the previous behavior. Treating None as null (just skip to the next iteration): follows industry standards. Raising a clear error such as “this does not accept None values”: it would still fail, but with a more helpful messa...