(cherry picked from commit 8debfa50)

``OPENSSL_VERSION_1_1`` was never defined in ``_hashopenssl.c``.

https://bugs.python.org/issue33936
(cherry picked from commit 724f1a57)
Co-authored-by: Christian Heimes <christian@python.org>

(cherry picked from commit 56a45142)

Co-authored-by: Hai Shi shihai1992@gmail.com

https://bugs.python.org/issue38168

This change skips parsing of email addresses where domains include a "@" character, which can be maliciously used since the local part is returned as a complete address. 

(cherry picked from commit 8cb65d13)

Excludes changes to Lib/email/_header_value_parser.py, which did not
exist in 2.7.
Co-authored-by: jpic <jpic@users.noreply.github.com>


https://bugs.python.org/issue34155

Fixes a build error with OpenSSL 1.1.0. There is already code in the
`_ssl.c` that handles all the weird cases of the NPN config macros (with
various OpenSSL & LibreSSL versions).
That code will provide a HAVE_NPN variable, which should be used in the
rest of the code to check whether (or what) to compile regarding NPN.

This change adds HAVE_NPN in the remaining places where it should have been
placed.
Signed-off-by: Alexandru Ardelean <ardeleanalex@gmail.com>


https://bugs.python.org/issue35264

If FormatMessageW() is passed the FORMAT_MESSAGE_FROM_SYSTEM flag
without FORMAT_MESSAGE_IGNORE_INSERTS, it will fail if there are
insert sequences in the message definition.
(cherry picked from commit a6563650)

The link we have points to the version from Unicode 6.0.0, dated 2010.
There have been numerous updates to it since then:
  https://www.unicode.org/reports/tr44/GH-Modifications

Change the link to one that points to the current version. Also, use HTTPS..
(cherry picked from commit 64c6ac74)
Co-authored-by: Greg Price <gnprice@gmail.com>

RuntimeError is now raised in this case.
(cherry picked from commit 526a0146)

https://bugs.python.org/issue37965

https://bugs.python.org/issue37965

Automerge-Triggered-By: @benjaminp
(cherry picked from commit 55aabee0)
Co-authored-by: Anonymous Maarten <madebr@users.noreply.github.com>

Fix file descriptors transfer in multiprocessing on FreeBSD: use
CMSG_SPACE() rather than CMSG_LEN(); see RFC 3542.

(cherry picked from commit d0b10a64)

Fixed wrong link to Telnet.open() method in telnetlib documentation.
(cherry picked from commit e0b6117e)
Co-authored-by: Michael Anckaert <michael.anckaert@sinax.be>

If this service had thoroughly vanished, we could just ignore the
test until someone gets around to either recreating such a service
or redesigning the test to somehow work locally.  The
`support.transient_internet` mechanism catches the failure to
resolve the domain name, and skips the test.

But in fact the domain snakebite.net does still exist, as do its
nameservers -- and they can be quite slow to reply.  As a result
this test can easily take 20-30s before it gets auto-skipped.

So, skip the test explicitly up front.
(cherry picked from commit 5b95a150)
Co-authored-by: Greg Price <gnprice@gmail.com>

[2.7] bpo-37730: Fix usage of NotImplemented instead of NotImplementedError in docs. (GH-15062). (GH-15133)

(cherry picked from commit ed5e8e06)
Co-authored-by: David H <dheiberg@mozilla.com>

(cherry picked from commit 93e8aa62)
Co-authored-by: Benjamin Peterson <benjamin@python.org>

(cherry picked from commit 79042ac4)
Co-authored-by: Tal Einat <taleinat@gmail.com>

(cherry picked from commit 2a3d4d9c)
Co-authored-by: Benjamin Peterson <benjamin@python.org>

(cherry picked from commit f6cdd3ff)
Co-authored-by: Hai Shi <shihai1992@gmail.com>

0 is a legal index.
(cherry picked from commit f8709e80)
Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>

Also fix a name misspelling.
(cherry picked from commit 45bc61b9)
Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>

(cherry picked from commit 2cd07920)
Co-authored-by: Benjamin Peterson <benjamin@python.org>

When building 2.7 on macOS without system header files installed in
``/usr/include``, a few extension modules dependent on system-supplied
third-party libraries were not being built, most notably zlib.
This situation arose in the past when building without the Command
Line Tools and the option to install header files in the traditional
system locations (like /usr/include).  As of macOS 10.14, the
header files are only available in an SDK so the problem addressed
here affects most 2.7 builds.

* Added documentation for textwrap.dedent behavior.
(cherry picked from commit eb97b921)
Co-authored-by: tmblweed <tmblweed@users.noreply.github.com>


https://bugs.python.org/issue30754

_PyWarnings_Init() only allocates memory once at startup but it is
not released at exit. Ignore this issue to be able to catch other
bugs more easily.

(cherry picked from commit 3b03b09f)
Co-authored-by: Benjamin Peterson <benjamin@python.org>

Fix test_wsgiref.testEnviron() to no longer depend on the environment
variables (don't fail if "X" variable is set).

testEnviron() now overrides os.environ to get a deterministic
environment. Test full TestHandler.environ content: not only a few
selected variables.
(cherry picked from commit 5150d327)
Co-authored-by: Victor Stinner <vstinner@redhat.com>

Add $(PyDebugExt) in "Killing any running python$(PyDebugExt).exe
instances...".

(cherry picked from commit c0295dba)

* regrtest: Add --cleanup option to remove "test_python_*" directories
  of previous failed test jobs.
* Add "make cleantest" to run "python -m test --cleanup".

(cherry picked from commit 47fbc4e4)

Rephrase and clarify that "the entire Python program exits when only daemon threads are left". This matches the documentation at https://docs.python.org/3/library/threading.htmlGH-thread-objects.
(cherry picked from commit bb110cc2)
Co-authored-by: mbarkhau <mbarkhau@gmail.com>

test_gdb no longer fails if it gets an "unexpected" message on
stderr: it now ignores stderr. The purpose of test_gdb is to test
that python-gdb.py commands work as expected, not to test gdb.

(cherry picked from commit e56a123f)

'\0' is the NUL byte not NULL..
(cherry picked from commit 7821b4c6)