On behalf of the Twisted contributors I announce the release candidate of Twisted 21.7.0

This is mostly a bugfix release.

Python 3.5 is no longer a supported platform.
The minimum supported platform is Python 3.6.7.

The notable features are:

- Python 3.10 beta is now a supported platform.
- twisted.web.template.renderElement() now accepts any IRequest implementer instead of only twisted.web.server.Request. Add type hints to twisted.web.template. (#10184)

The release and NEWS file is available for review at

    https://github.com/twisted/twisted/pull/1614/files

Release candidate documentation is available at

    https://twisted--1614.org.readthedocs.build/en/1614/

Wheels for the release candidate are available on PyPI

    https://pypi.org/project/Twisted/21.7.0rc1/

    python -m pip install Twisted==21.7.0rc1

Please test it and report any issues.
If nothing comes up in 1 week, 21.7.0 will be released based on the latest release candidate.

Many thanks to everyone who had a part in Twisted - the supporters of the Twisted Software Foundation, the developers, and all the people testing and building great things with Twisted!

--
Adi Roiban