`StrEnum` does not exist in 3.8, so use original `(str, enum.Enum)` bases.

(cherry picked from commit 62e40d8)

Co-authored-by: Ethan Furman <ethan@stoneleaf.us>

(cherry picked from commit 9c4eac7)

Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>

(cherry picked from commit 22b7616)

Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>

…ain_run_module (GH-21956) (#22397)

Closes bpo issue 41602.
(cherry picked from commit a68a2ad)

Co-authored-by: Thomas Grainger <tagrain@gmail.com>

'Python Shell' may have contributed to some beginners confusing 'IDLE' with ' Python'.
(cherry picked from commit 05cc881)

Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>

The existing line is easily read as being incomplete.
(cherry picked from commit 00eb063)

Co-authored-by: Emmanuel Arias <eamanu@yaerobi.com>

…typing (GH-22340)

This shows users that they can use the actual types. Using deprecated types is confusing.

This also prefers colections.abc.Sized instead of the alias typing.Sized. I guess the aliases were created to make it convenient to import all collections related types from the same place.

This should be backported to 3.9.

Automerge-Triggered-By: @gvanrossum
(cherry picked from commit d9ab95f)

Co-authored-by: Andre Delfino <adelfino@gmail.com>

…9337)

(cherry picked from commit ff9147d)

Co-authored-by: Jan Mazur <16736821+mzr@users.noreply.github.com>

(cherry picked from commit 24ba3b0)

Co-authored-by: Dong-hee Na <donghee.na92@gmail.com>

In the "Sequences (Tuples/Lists)" section, add
"How do you remove multiple items from a list".
(cherry picked from commit 5b0181d)

Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>

From `In particularly,` to `In particular,`
(cherry picked from commit 6329893)

Co-authored-by: Max Smolens <msmolens@users.noreply.github.com>

(cherry picked from commit 20ce62f)

Co-authored-by: Campbell Barton <ideasman42@gmail.com>

* Correct at 2 places in email module
(cherry picked from commit 9cd01ec)

Co-authored-by: Hansraj Das <raj.das.136@gmail.com>

Automerge-Triggered-By: @gvanrossum
(cherry picked from commit d4b9edd)

Co-authored-by: Andre Delfino <adelfino@gmail.com>

…en a default namespace was defined. (GH-22474) (GH-22507)

(cherry picked from commit 6a412c9)

…ths (GH-20554)

(cherry picked from commit f97e42e)

Co-authored-by: Ram Rachum <ram@rachum.com>

… methods (GH-22418)

(cherry picked from commit 5230131)

Co-authored-by: Ram Rachum <ram@rachum.com>

Missed this occurrence before, sorry. Also changed "the PEP" to "PEP".

Automerge-Triggered-By: @gvanrossum
(cherry picked from commit 3fe6148)

Co-authored-by: Andre Delfino <adelfino@gmail.com>

… in the symtable module (GH-22391). (GH-22528)

(cherry picked from commit fb0a465)

Co-authored-by: Pablo Galindo <Pablogsal@gmail.com>

…H-22524)

This changes a few occurrences left behind by GH-22340.

Automerge-Triggered-By: @gvanrossum
(cherry picked from commit 7f54e56)

Co-authored-by: Andre Delfino <adelfino@gmail.com>

…H-22288)

(cherry picked from commit a33f2c2)
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

Use an unique identifier for the different grammars documented using
the Sphinx productionlist markup.

productionlist markups of the same grammar, like "expressions" or
"compound statements", use the same identifier "python-grammar".
(cherry picked from commit 8af239e)

Co-authored-by: Victor Stinner <vstinner@python.org>

Doc/requirements.txt becomes the reference for packages and package
versions needed to build the Python documentation.

* Doc/Makefile now uses Doc/requirements.txt
* .travis.yml now uses "make env" of Doc/Makefile
* Update Sphinx to version 2.4.4

(cherry picked from commit 8394500)

(cherry picked from commit 22b7616)

Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>

The existing line is easily read as being incomplete.
(cherry picked from commit 00eb063)

Co-authored-by: Emmanuel Arias <eamanu@yaerobi.com>

…typing (GH-22340)

This shows users that they can use the actual types. Using deprecated types is confusing.

This also prefers colections.abc.Sized instead of the alias typing.Sized. I guess the aliases were created to make it convenient to import all collections related types from the same place.

This should be backported to 3.9.

Automerge-Triggered-By: @gvanrossum
(cherry picked from commit d9ab95f)

Co-authored-by: Andre Delfino <adelfino@gmail.com>