* Apply PEP8 naming convention.
* Add additional tests to get coverage (close?) to 100%.
* Update to more meaningful names.
* Switch to ttk widgets and revise imports.
* Split toplevel class into a window class and frame class(es).

PR11330 is for the PEP8 naming conventions.

I am going to merge on the presumption that you will follow through at least with more tests.  Currently missing other than mac-code, according to coverage output: switch from 'advanced to basic and calls to final_key_selected, build_key_string, get_modifiers, and translate_key.  The last should become a standalone function.

I believe I have encountered a bug.  Change a key binding.  Cancel. Re-open config dialog.  Try to change back.  It says original binding is in use -- which it is if one closes IDLE and reopens, or opens a different instance.  It seems that cancel is not properly undoing the temporary change.

If you submit further PRs for this issue, the blurb will need to be changed as blurbs are for issues, not PRs.

New changeset 55698cc39549523cafc13cc8dd47960d8f73a59f by Terry Jan Reedy (Cheryl Sabella) in branch 'master':
bpo-35598: IDLE: Update config_key.py with PEP8 names (GH-11330)
https://github.com/python/cpython/commit/55698cc39549523cafc13cc8dd47960d8f73a59f

New changeset 4c7f34f73d2d16303798fc4a7043e641cee58e51 by Miss Islington (bot) in branch '3.7':
bpo-35598: IDLE: Update config_key.py with PEP8 names (GH-11330)
https://github.com/python/cpython/commit/4c7f34f73d2d16303798fc4a7043e641cee58e51

PR11360 adds tests to increase coverage.  There isn't any refactor (moving translate_key) as part of this.  I also didn't add any GUI-related tests against the buttons, entry, or listbox, except for the cancel key (in case that helps with the new bug reported).

New changeset b0a6196ffd58ff91462191f426706897dc920eee by Terry Jan Reedy (Cheryl Sabella) in branch 'master':
bpo-35598: IDLE: Increase test coverage for config_key.py (#11360)
https://github.com/python/cpython/commit/b0a6196ffd58ff91462191f426706897dc920eee

New changeset 34aadec448f373b95653318e91f6f959354ffa89 by Miss Islington (bot) in branch '3.7':
bpo-35598: IDLE: Increase test coverage for config_key.py (GH-11360)
https://github.com/python/cpython/commit/34aadec448f373b95653318e91f6f959354ffa89

PR11365 revises the imports and switches to ttk widgets.

New changeset 4bd79c38efe3cc0a3c724605cf9474e2d1b6b6e2 by Terry Jan Reedy (Cheryl Sabella) in branch 'master':
bpo-35598: IDLE: Switch config_key dialog to ttk widgets (GH-11365)
https://github.com/python/cpython/commit/4bd79c38efe3cc0a3c724605cf9474e2d1b6b6e2

New changeset d2694d47682b84dafef1c172ede7ad16d3b8bbd8 by Miss Islington (bot) in branch '3.7':
bpo-35598: IDLE: Switch config_key dialog to ttk widgets (GH-11365)
https://github.com/python/cpython/commit/d2694d47682b84dafef1c172ede7ad16d3b8bbd8

PR11392 is the first refactor.  It moves translate_key to the module level and also moves the definitions of the key tuples to the module level since they are used in more than one place (and they don't change).

As a side note, I'll do the refactoring over several PRs to try to make it manageable to review.

(PR11377 was the first version of this, but somehow I really messed it and couldn't get it back.)

New changeset b4ea8bb080f63ef27682f3f9bbaa4d12a83030b1 by Terry Jan Reedy (Cheryl Sabella) in branch 'master':
bpo-35598: IDLE - Globalize some config_key objects (GH-11392)
https://github.com/python/cpython/commit/b4ea8bb080f63ef27682f3f9bbaa4d12a83030b1

New changeset 74e46483773fa2ed03ed02f1b5e3fb0a4691535e by Miss Islington (bot) in branch '3.7':
bpo-35598: IDLE - Globalize some config_key objects (GH-11392)
https://github.com/python/cpython/commit/74e46483773fa2ed03ed02f1b5e3fb0a4691535e

This issue looks complete to me unless there is something simple not previously mentioned.

Fixing cancel would be a separate issue.

Separating window and frame needs separate discussion on a separate issue, and is not a priority now.  Model popups are different from independent listed windows, so I an not sure what we will want to do for a future tabbed window.

A more immediate concern to me is finishing ttk conversion, including using ttk frames for ttk widgets.  (See #33987 for why.)

Terry,

I just saw your note about waiting to split this into a Window and Frame class, which was after I had already gotten the PR ready.  I've been mostly offline for the past few days, so I had been working on those changes locally with the intent of pushing them once I was back online.  I understand if it's not a priority to review.  My main goal in splitting them was more for readability rather than for being able to add it to a Tabbed window.  As a follow up to this refactor, I had hoped to split the Basic and Advanced frames into their own tabs, mostly to clean up the create_widgets and to organize the supporting functions.

Anyway, PR11427 refactors the main frame from the window.

I moved PR 11427 to new issue #35675.