Twisted Drops Python 2.7 Support

With the open-source Python community at large dropping Python 2.7 support in their projects, Twisted has decided to do the same. Twisted 20.3.0, the most recently released version, is the final release to offer Python 2.7 support.

Despite the break, the compatibility policy still applies. This means that if your code works with Twisted 20.3 on Python 2.7 and 3.5+, that updating your Twisted on Python 3 up to a theoretical 21.3 would not require changes that would make Python 2.7 + Twisted 20.3 stop working, despite a theoretical Twisted 21.3 not supporting 2.7. (This is, of course, in an ideal situation -- regressions and changes that are excepted from the policy such as security fixes do occur. Testing your applications on Twisted prereleases can help catch places where this happens, so, please do!)

- Amber (HawkOwl)

Twisted 20.3.0 Released

On behalf of Twisted Matrix Laboratories, I am honoured to announce the release of Twisted 20.3! The highlights of this release are:

• curve25519-sha256 key exchange algorithm support in Conch.
• "openssh-key-v1" key format support in Conch.
• Security fixes to twisted.web, including preventing request smuggling attacks and rejecting malformed headers. CVE-2020-10108 and CVE-2020-10109 were assigned for these issues, see the NEWS file for full details.
• twist dns --secondary now works on Python 3.
• The deprecation of twisted.news.
• ...and various other fixes, with 28 tickets closed in total. 

This is the final Twisted release to support Python 2.7.

You can find the downloads at <https://pypi.org/project/Twisted> (or alternatively <https://twistedmatrix.com/trac/wiki/Downloads>). The NEWS file is also available at <https://github.com/twisted/twisted/blob/twisted-20.3.0/NEWS.rst>.
Many thanks to everyone who had a part in this release — the supporters of the Twisted Software Foundation, the developers who contributed code as well as documentation, and all the people building great things with Twisted!
- hawkowl