Python 3.8.0b4 is now available for testing

It's time for the last beta release of Python 3.8. Go find it at:
https://www.python.org/downloads/release/python-380b4/ 

This release is the last of four planned beta release previews. Beta release previews are intended to give the wider community the opportunity to test new features and bug fixes and to prepare their projects to support the new feature release. The next pre-release of Python 3.8 will be 3.8.0c1, the first release candidate, currently scheduled for 2019-09-30.
 

Call to action

We strongly encourage maintainers of third-party Python projects to test with 3.8 during the beta phase and report issues found to the Python bug tracker as soon as possible. Please note this is the last beta release, there is not much time left to identify and fix issues before the release of 3.8.0. If you were hesitating trying it out before, now is the time.
While the release is planned to be feature complete entering the beta phase, it is possible that features may be modified or, in rare cases, deleted up until the start of the release candidate phase (2019-09-30). Our goal is have no ABI changes after beta 3 and no code changes after 3.8.0c1, the release candidate. To achieve that, it will be extremely important to get as much exposure for 3.8 as possible during the beta phase.

Please keep in mind that this is a preview release and its use is not recommended for production environments. 

Acknowledgments

Many developers worked hard for the past four weeks to squash remaining bugs, some requiring non-obvious decisions. Many thanks to the most active, namely Raymond Hettinger, Steve Dower, Victor Stinner, Terry Jan Reedy, Serhiy Storchaka, Pablo Galindo Salgado, Tal Einat, Zackery Spytz, Ronald Oussoren, Neil Schemenauer, Inada Naoki, Christian Heimes, and Andrew Svetlov.

3.8.0 would not reach the Last Beta without you. Thank you!

Inspect PyPI event logs to audit your account's and project's security

To help you check for security problems, PyPI is adding an advanced audit log of user actions beyond the current (existing) journal. This will, for instance, allow publishers to track all actions taken by third party services on their behalf.

This beta feature is live now on PyPI and on Test PyPI.

Background:
We're further increasing the security of the Python Package Index with another new beta feature: an audit log of sensitive actions that affect users and projects. This is thanks to a grant from the Open Technology Fund, coordinated by the Packaging Working Group of the Python Software Foundation.

Details:

Project security history display, listing
events (such as "file removed from release version 1.0.1")
with user, date/time, and IP address for each event.

We're adding a display so you can look at things that have happened in your user account or project, and check for signs someone's stolen your credentials.

In your account settings, you can view a log of sensitive actions from the last two weeks that are relevant to your user account, and if you are an Owner at least one project on PyPI, you can go to that project's Manage Project page to view a log of sensitive actions (performed by any user) relevant to that project. (And PyPI site administrators are able to view the full audit log for all users and all projects.)

Please help us test this, and report issues.

User security history display, listing
events (such as "API token added")
with additional details (such as token scope), date/time,
and IP address for each event.

In beta:
We're still refining this and may fail to log, or to properly display, events in the audit log. And the sensitive event logging and display starting on 16 August 2019, so you won't see sensitive events from before that date. (Read more technical details about implementation in the GitHub issue.)

Next:
We're continuing to refine all our beta features, while working on accessibility improvements and starting to work on localization on PyPI. Follow our progress reports in more detail on Discourse.

Python 3.8.0b3 is now available for testing

It's time for a new Python preview:
https://www.python.org/downloads/release/python-380b3/ 

This release is the third of four planned beta release previews. Beta release previews are intended to give the wider community the opportunity to test new features and bug fixes and to prepare their projects to support the new feature release. The next pre-release of Python 3.8 will be 3.8.0b4, the last beta release, currently scheduled for 2019-08-26.
 

Call to action

We strongly encourage maintainers of third-party Python projects to test with 3.8 during the beta phase and report issues found to the Python bug tracker as soon as possible. While the release is planned to be feature complete entering the beta phase, it is possible that features may be modified or, in rare cases, deleted up until the start of the release candidate phase (2019-09-30). Our goal is have no ABI changes after beta 3 and no code changes after 3.8.0rc1, the release candidate. To achieve that, it will be extremely important to get as much exposure for 3.8 as possible during the beta phase.

Please keep in mind that this is a preview release and its use is not recommended for production environments. 

Last beta coming

Beta 4 can only be released if all “Release blocker” and “Deferred blocker” issues on bugs.python.org for 3.8.0 are resolved. The core team will prioritize fixing those for the next four weeks.
 

Acknowledgements

Thanks to our binary builders, Ned and Steve, who were very quick today to get the macOS and Windows installers ready. The Windows story in particular got pretty magical, it’s now really fully automatic end-to-end.

Thanks to Victor for vastly improving the reliability of multiprocessing tests since Beta 2.

Thanks to Pablo for keeping the buildbots green.