Release date: Dec. 18, 2019

This is an early developer preview of Python 3.9

Major new features of the 3.9 series, compared to 3.8

Python 3.9 is still in development. This releasee, 3.9.0a2 is the second of six planned alpha releases. Alpha releases are intended to make it easier to test the current state of new features and bug fixes and to test the release process. During the alpha phase, features may be added up until the start of the beta phase (2020-05-18) and, if necessary, may be modified or deleted up until the release candidate phase (2020-08-10). Please keep in mind that this is a preview release and its use is not recommended for production environments.

Many new features for Python 3.9 are still being planned and written. Among the new major new features and changes so far:

• PEP 602, Python adopts a stable annual release cadence
• BPO 38379, garbage collection does not block on resurrected objects;
• BPO 38692, os.pidfd_open added that allows process management without races and signals;
• A number of standard library modules (audioop, ast, grp, _hashlib, pwd, _posixsubprocess, random, select, struct, termios, zlib) are now using the stable ABI defined by PEP 384.
• (Hey, fellow core developer, if a feature you find important is missing from this list, let Łukasz know.)

The next pre-release of Python 3.9 will be 3.9.0a3, currently scheduled for 2020-01-13.

More resources

• Online Documentation
• PEP 569, 3.9 Release Schedule
• Report bugs at https://bugs.python.org.
• Help fund Python and its community.

And now for something completely different

At the Registry Office. Marriages division.

Man: Er, excuse me, I want to get married.
Registrar: I'm afraid I'm already married, sir.
Man: Er, no, no. I just want to get married.
Registrar: I could get a divorce, I suppose, but it'll be a bit of a wrench.
Man: Er, no, no. That wouldn't be necessary because...
Registrar: You see, would you come to my place or should I have to come to yours, because I've just got a big mortgage.
Man: No, no, I want to get married here.
Registrar: Oh dear. I had my heart set on a church wedding.
Man: Look, I just want you to marry me... to...
Registrar: I want to marry you too sir, but it's not as simple as that. You sure you want to get married?
Man: Yes. I want to get married very quickly.
Registrar: Suits me, sir. Suits me.
Man: I don't want to marry you!
Registrar: There is such a thing as breach of promise, sir.
Man: Look, I just want you to act as registrar and marry me.
Registrar: I will marry you sir, but please make up your mind. Please don't trifle with my affections.

Full Changelog