Release Date: Feb. 16, 2021

This is the release candidate of the eight maintenance release of Python 3.8

Note: The release you're looking at is Python 3.8.8rc1, a bugfix release for the legacy 3.8 series. Python 3.11 is now the latest feature release series of Python 3. Get the latest release of 3.11.x here.

3.8.8rc1 introduces two security fixes:

• bpo-42967: Fix web cache poisoning vulnerability by defaulting the query args separator to &, and allowing the user to choose a custom separator.

• bpo-42938: Avoid static buffers when computing the repr of ctypes.c_double and ctypes.c_longdouble values.

Major new features of the 3.8 series, compared to 3.7

• PEP 572, Assignment expressions
• PEP 570, Positional-only arguments
• PEP 587, Python Initialization Configuration (improved embedding)
• PEP 590, Vectorcall: a fast calling protocol for CPython
• PEP 578, Runtime audit hooks
• PEP 574, Pickle protocol 5 with out-of-band data
• Typing-related: PEP 591 (Final qualifier), PEP 586 (Literal types), and PEP 589 (TypedDict)
• Parallel filesystem cache for compiled bytecode
• Debug builds share ABI as release builds
• f-strings support a handy = specifier for debugging
• continue is now legal in finally: blocks
• on Windows, the default asyncio event loop is now ProactorEventLoop
• on macOS, the spawn start method is now used by default in multiprocessing
• multiprocessing can now use shared memory segments to avoid pickling costs between processes
• typed_ast is merged back to CPython
• LOAD_GLOBAL is now 40% faster
• pickle now uses Protocol 4 by default, improving performance

There are many other interesting changes, please consult the "What's New" page in the documentation for a full list.

More resources

• Online Documentation
• PEP 569, 3.8 Release Schedule
• Report bugs at https://bugs.python.org.
• Help fund Python and its community.

Windows users

• The binaries for AMD64 will also work on processors that implement the Intel 64 architecture. (Also known as the "x64" architecture, and formerly known as both "EM64T" and "x86-64".)
• There are now "web-based" installers for Windows platforms; the installer will download the needed software components at installation time.
• There are redistributable zip files containing the Windows builds, making it easy to redistribute Python as part of another software package. Please see the documentation regarding Embedded Distribution for more information.

macOS users

• For Python 3.8, we provide one installer: 64-bit-only that works on macOS 10.9 (Mavericks) and later systems.
• Please read the "Important Information" displayed during installation for information about SSL/TLS certificate validation and the running the "Install Certificates.command".

And now for something completely different

Voice Over (Michael Palin): This is Ken Clean-Air Systems, the great white hope of the British boxing world. After three fights - and only two convictions - his manager believes that Ken is now ready to face the giant American, Satellite Five.
Manager (Graham Chapman): The great thing about Ken is that he's almost totally stupid.
(Cut back to Ken jogging, the early morning sun filtering through the trees.)
Voice Over: Every morning, he jogs the forty-seven miles from his two-bedroomed, eight-bathroom, six-up-two-down, three-to-go-house in Reigate, to the Government's Pesticide Research Centre at Shoreham. Nobody knows why.

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