(cherry picked from commit ce75df30)
Co-authored-by: ValeriyaSinevich <valeriya.sinevich@phystech.edu>

(cherry picked from commit 11eb1a94)
Co-authored-by: Berker Peksag <berker.peksag@gmail.com>

Mathematically, bitwise operations on integers behave as if there were an
infinite number of sign bits. Pragmatically, that gives the same answer as
using one extra sign bit for the bitwise logical operations.
(cherry picked from commit b4bc5cab)
Co-authored-by: Sanyam Khurana <8039608+CuriousLearner@users.noreply.github.com>

(cherry picked from commit 8fe9eed9)
Co-authored-by: Dong-hee Na <donghee.na92@gmail.com>

Clarify how to bind to all interfaces using socket
(cherry picked from commit 95dfb9c3)
Co-authored-by: johnthagen <johnthagen@users.noreply.github.com>

<!-- issue-number: bpo-5978 -->
https://bugs.python.org/issue5978
<!-- /issue-number -->
(cherry picked from commit 937fb55d)
Co-authored-by: Andrés Delfino <adelfino@gmail.com>

(cherry picked from commit 612dbefe)
Co-authored-by: Berker Peksag <berker.peksag@gmail.com>

/usr/local/lib/pythonX.Y is used by Homebrew's Python already.
(cherry picked from commit 3e7d18a5)
Co-authored-by: INADA Naoki <methane@users.noreply.github.com>

Also, update the list of exceptions that may raised by PyMarshal_*
functions. We usually don't document exceptions raised by a
function, but in this case most of them were already documented
in C API and standard library documentation.
(cherry picked from commit defcffdf)
Co-authored-by: Berker Peksag <berker.peksag@gmail.com>

Enable and fix SMTPUTF8SimTests in test_smtplib.

The tests for SMTPUTF8SimTests in test_smtplib.py were not actually
being run because test_smtplib was still using the 'test_main' pattern,
and the class was never added to test_main.

Additionally, one of the tests needed to be moved to the non-UTF8 server
class because it relies on the server not being UTF-8 compatible (and it
had a bug in in).
(cherry picked from commit 48ed88a9)
Co-authored-by: chason <chason@gmail.com>

On Windows, passing a negative value to local results in an OSError because localtime_s on Windows does not support negative timestamps. Unfortunately this means that fold detection for timestamps between 0 and max_fold_seconds will result in this OSError since we subtract max_fold_seconds from the timestamp to detect a fold. However, since we know there haven't been any folds in the interval [0, max_fold_seconds) in any timezone, we can hackily just forego fold detection for this time range on Windows.
(cherry picked from commit 96d1e69a)
Co-authored-by: Ammar Askar <ammar_askar@hotmail.com>

(cherry picked from commit c0f0a766)
Co-authored-by: Aaron Ang <aaronang@users.noreply.github.com>

The script will exit with the number 0 (zero), instead of the letter O.
(cherry picked from commit 95d34c2a)
Co-authored-by: Mariatta <Mariatta@users.noreply.github.com>

(cherry picked from commit 06ca3f0c)
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

Now base64.Error is always raised instead of UnboundLocalError or
OverflowError.
(cherry picked from commit ac0b3c2f)
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

(cherry picked from commit aba24ff3)
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

(cherry picked from commit db8e3a1e)
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

(cherry picked from commit 147d9551)
Co-authored-by: jdemeyer <jdemeyer@cage.ugent.be>

(cherry picked from commit bde782bb)
Co-authored-by: Matthias Bussonnier <bussonniermatthias@gmail.com>

(cherry picked from commit 3fe5cccb)

imaplib now allows MOVE command in IMAP4.uid() (RFC 6851:
IMAP MOVE Extension) and potentially as a name of supported
method of IMAP4 object.
(cherry picked from commit caa331d4)
Co-authored-by: Matěj Cepl <mcepl@cepl.eu>

When Python is installed on Windows, python -m test test_tools failed
because it tried to run Tools\scripts\2to3.py which requires an
argument. Skip this script. On other platforms or on Windows but when
run from source code (not installed), the script is called "2to3"
instead of "2to.py" and so was already skipped.

Modify also the unit test to unload all modules which have been
loaded by the test.
(cherry picked from commit 752d4b75)
Co-authored-by: Victor Stinner <vstinner@redhat.com>

(cherry picked from commit 7a3056fa)
Co-authored-by: Berker Peksag <berker.peksag@gmail.com>

(cherry picked from commit d04f46c5)
Co-authored-by: Berker Peksag <berker.peksag@gmail.com>

(cherry picked from commit e271ca78)
(cherry picked from commit c75c1e0e)

(cherry picked from commit 96136092)
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

(cherry picked from commit cb9c299a)
Co-authored-by: Andrés Delfino <adelfino@gmail.com>

(cherry picked from commit 938045f3)
Co-authored-by: Bo Bayles <bbayles@gmail.com>

(cherry picked from commit 56868f94)
Co-authored-by: jdemeyer <jdemeyer@cage.ugent.be>

(cherry picked from commit a692efe4)
Co-authored-by: Xtreak <tirkarthi@users.noreply.github.com>

The test failed on my laptop because the busy loop took 15.9 ms
whereas the test expects at least 20 ms. Modify test_process_time()
as test_thread_time() has been modified recently: only require 15 ms
instead of 20 ms.
(cherry picked from commit e78dace8)
Co-authored-by: Victor Stinner <vstinner@redhat.com>

Py_Main() can again be called after Py_Initialize(), as in Python
3.6. The new configuration is ignored, except of
_PyMainInterpreterConfig.argv which is used to update sys.argv.
(cherry picked from commit fb47bca9)
Co-authored-by: Victor Stinner <vstinner@redhat.com>

The parentheses were incorrect.
(cherry picked from commit cb5f3fdb)
Co-authored-by: Aaqa Ishtyaq <aaqaishtyaq@gmail.com>

Cherry-picked from 2c5c0a36

(cherry picked from commit b12112b5)

Increase the timeout: give timeout x 4 instead of timeout x 2 to
threads to wait until the Event is set, but reduce the sleep from 500
ms to 250 ms. So the test should be more reliable and faster!
(cherry picked from commit 81950495)
Co-authored-by: Victor Stinner <vstinner@redhat.com>

* bpo-34130: Fix test_signal.test_socket() (GH-8326)

test_signal.test_socket(): On Windows, sometimes even if the C signal handler
succeed to write the signal number into the write end of the socketpair, the
test fails with a BlockingIOError on the non-blocking read.recv(1) because the
read end of the socketpair didn't receive the byte yet.

Fix the race condition on Windows by setting the read end as blocking.

(cherry picked from commit 99bb6df6)

* bpo-34130: Fix test_signal.test_warn_on_full_buffer() (GH-8327)

On Windows, sometimes test_signal.test_warn_on_full_buffer() fails to
fill the socketpair buffer. In that case, the C signal handler
succeed to write into the socket, it doesn't log the expected send
error, and so the test fail.

On Windows, the test now uses a timeout of 50 ms to fill the
socketpair buffer to fix this race condition.

Other changes:

* Begin with large chunk size to fill the buffer to speed up the
  test.
* Add error messages to assertion errors to more easily identify
  which assertion failed.
* Don't set the read end of the socketpair as non-blocking.

(cherry picked from commit 686b4b5f)

(cherry picked from commit feabae96)
Co-authored-by: Raymond Hettinger <rhettinger@users.noreply.github.com>