This looks like the only place that proto 4 framing gets exercised
so leave it as part of the PGO task.

Mark some individual tests to skip when --pgo is used.  The tests
marked increase the PGO task time significantly and likely don't
help improve optimization of the final executable.

Use cffi to access a C API in Python.

When scanning the string, most characters are valid, so
checking for invalid characters first means never needing
to check the value of strict on valid strings, and only
needing to check it on invalid characters when doing
non-strict parsing of invalid strings.

This provides a measurable reduction in per-character
processing time (~11% in the pre-merge patch testing).

Deprecate the parser module and add a deprecation warning triggered on import and a warning block in the documentation.





https://bugs.python.org/issue37268



Automerge-Triggered-By: @pablogsal

They pass with tk 8.5.9 (Azure) but fail with the 8.6.x we install.

https://bugs.python.org/issue36044



Automerge-Triggered-By: @zooba

* bpo-37697: Sync with importlib_metadata 0.19

* Run make regen-importlib

* 📜🤖 Added by blurb_it.

Use an example shell interaction in the sample and better labels for shell elements.

The boxes for the font and highlight samples are now constrained by the overall config dialog size.  They gain scrollbars when the when a large font size makes the samples too large for the box.

Add __all__ to tkinter.__init__ and submodules.  Replace 'import *'
with explicit imports in some submodules.

Previously, pyc files in the embeddable distribution reported their
location as <build path>/<file stem>.py. This causes a little confusion
when interpreting stack traces as the file is in a (almost certainly)
incorrect location, and lacks the full relative path to Lib (e.g.
email/mime/image.py will only show image.py).

This change preserves the Lib relative location of the source file as a
path so that stack traces are (hopefully) less misleading and more
informative.
Co-Authored-By: Kyle Stanley <aeros167@gmail.com>

Prior to this change the guard on an 'elif' used an assignment expression whose value was used in a later 'else' block, causing some confusion for people.

(Discussion on Twitter: https://twitter.com/brettsky/status/1153861041068994566.)

Automerge-Triggered-By: @brettcannon

* Fix the formatting in the documentation of the tostring() functions.

* bpo-34160: Document that the tostring() and tostringlist() functions also preserve the attribute order now.

* bpo-34160: Add an explanation of how users should deal with the attribute order.

* bpo-37399: Correctly attach tail text to the last element/comment/pi, even when comments or pis are discarded.
Also fixes the insertion of PIs when "insert_pis=True" is configured for a TreeBuilder.

Verify that it appears to find roughly the right number of tests in the stdlib's testsuite.

Stop depending on tkinter import *.