netrc file format doesn't support quotes and escapes.

See https://linux.die.net/man/5/netrc

This was possible before.  GH-1560 introduced a regression after 3.6.2 got
released where only sequences were accepted now.  This commit addresses this
problem.

bpo-31602: Fix an assertion failure in zipimporter.get_source() in case of a bad zlib.decompress() (GH-3784)

While a rare potential failure (it requires swapping out zlib.decompress() itself and forcing it to return a non-bytes object), this change prevents a potential C-level assertion failure and instead substitutes it with an exception.

Thanks to Oren Milman for the patch.

Add optional argument `compressed` to `zipapp.create_archive`, and add
option `--compress` to the command line interface of `zipapp`.

bpo-11063, bpo-20519: avoid ctypes and improve import time for uuid.

bpo-31478: Fix an assertion failure in random.seed() in case a seed has a bad __abs__() method. (#3596)

Class execution requires that __prepare__() methods return
a proper execution namespace. Check for that immediately
after calling __prepare__(), rather than passing it through
to the code execution machinery and potentially triggering
SystemError (in debug builds) or a cryptic TypeError
(in release builds).

Patch by Oren Milman.

Non-regression tests for the Expat 2.2.3 UTF-8 decoder bug.

now becames exhausted after advancing the groupby iterator.

bpo-31505: Fix an assertion failure in json, in case _json.make_encoder() received a bad encoder() argument. (#3643)

* Give pdb.set_trace() an optional `header` argument

* What's new.

* Give pdb.set_trace() an optional `header` argument

* What's new.

Affected classes are bytearray, array, deque, defaultdict, count and repeat.

Previously ensurepip would always report success, even if the
pip installation failed.

This fixes a regression from Python 2.  To get optional subparsers,
use the new parameter ``add_subparsers(required=False)``.

Patch by Anthony Sottile.

* bpo-31479: Always reset the signal alarm in tests

Use "try: ... finally: signal.signal(0)" pattern to make sure that
tests don't "leak" a pending fatal signal alarm.

* Move two more alarm() calls into the try block

Fix also typo: replace signal.signal(0) with signal.alarm(0)

* Move another signal.alarm() into the try block

bpo-31293: Fix crashes in truediv and mul of a timedelta by a float with a bad as_integer_ratio() method. (#3227)

bpo-31315: Fix an assertion failure in imp.create_dynamic(), when spec.name is not a string. (#3257)

* Trivial cleanups following bpo-31370

* Also cleanup the "importlib._bootstrap_external" module

* bpo-31499, xml.etree: Fix xmlparser_gc_clear() crash

xml.etree: xmlparser_gc_clear() now sets self.parser to NULL to prevent a
crash in xmlparser_dealloc() if xmlparser_gc_clear() was called previously
by the garbage collector, because the parser was part of a reference cycle.
Co-Authored-By: Serhiy Storchaka <storchaka@gmail.com>

bpo-31482: Missing bytes support for random.seed() version 1 #3614

Signed-off-by: Christian Heimes <christian@python.org>

Replaces PROTOCOL_TLSv* and PROTOCOL_SSLv23 with PROTOCOL_TLS_CLIENT and
PROTOCOL_TLS_SERVER.
Signed-off-by: Christian Heimes <christian@python.org>

SSLSocket.wrap_bio() and SSLSocket.wrap_socket() hard-code SSLObject and
SSLSocket as return types. In the light of future deprecation of
ssl.wrap_socket() module function and direct instantiation of SSLSocket,
it is desirable to make the return type of SSLSocket.wrap_bio() and
SSLSocket.wrap_socket() customizable.
Signed-off-by: Christian Heimes <christian@python.org>

Give 30 seconds to join_process(), instead of 5 or 10 seconds, to
wait until the process completes.

Call the .join() method of threading.Timer timers to prevent the
"threading_cleanup() failed to cleanup 1 threads" warning.

New -n flag allow overriding localhost with custom value,
for example to run from containers.

join_thread() joins a thread but raises an AssertionError if the
thread is still alive after timeout seconds.

Call thread.join() to prevent the "dangling thread" warning.

Use _thread.count() to wait until threads exit. The new context
manager prevents the "dangling thread" warning.

Call thread.join() to prevent the "dangling thread" warning.

* Avoid calling "PyObject_GetAttrString()" (and potentially executing user code) with a live exception set.

* Ignore only AttributeError on attribute lookups in ElementTree.XMLParser() and propagate all other exceptions.

bpo-31471: Fix assertion failure in subprocess.Popen() on Windows, in case env has a bad keys() method. (#3580)