Support keyring.get_username_and_password

[zooba]

The next release of keyring will include a get_username_and_password API that allows backends to return both a username and password for a URL.

By updating twine to use this API, we can enable backends for private feeds to use other mechanisms besides simple username/passwords to authenticate users.

[sigmavirus24]

By updating twine to use this API, we can enable backends for private feeds to use other mechanisms besides simple username/passwords to authenticate users.

I don't understand this. Could you please provide a more thorough explanation of why we want to use a new API of a package that doesn't seem to be released yet?

[zooba]

Could you please provide a more thorough explanation of why we want to use a new API of a package that doesn't seem to be released yet?

The short reason is that there's no point in us releasing the package before the critical tools can use it, otherwise we tell people to "install twine and and it'll just work" and it doesn't actually work. If you're going to wait until we have this in play, then it'll never happen.