Item 11 from #33610.
Use read-only Text instead of Label for context. 

* Change widget type from Label to Text and remove Label-only arguments.
* Add height and state arguments.
* Change widget name from self.label to self.context.
* Tests: change widget name and method for getting text.

This makes detecting the context line a user clicks on slightly easier.  See new issue #33768 for discussion.  I am not sure now I would do this just for this reason, without trying with the label first.

Using a text also allows us to experiment with tagging the context keyword somehow, to see if it seems like an improvement.  Perhaps make it bold, or underlined, or the normal keyword color, or some variant thereof (grayed?).

So I am inclined to go ahead.  I did notice that most of the patch is straightforward substitution.  To me, this suggests that the code is pretty good.  Also, I think change 'label' (implentation) to 'context' (purpose) is a good change by itself.  I would keep this even if we reverted to using Label.

To your point, when I was adding the colors to configuration for context, I wondered if having context as a text widget could somehow use the colorizer.  I didn't really look into it, but it did seem like it might make sense to keep all the foreground text colors the same as they are in the editor.

New changeset b609e687a076d77bdd687f5e4def85e29a044bfc by Terry Jan Reedy (Cheryl Sabella) in branch 'master':
bpo-33763: IDLE: Replace label widget with text widget in code context (GH-7367)
https://github.com/python/cpython/commit/b609e687a076d77bdd687f5e4def85e29a044bfc

New changeset ffe29dbcd96dc2fbda212f8335908fa1bc8ed893 by Miss Islington (bot) in branch '3.6':
bpo-33763: IDLE: Replace label widget with text widget in code context (GH-7367)
https://github.com/python/cpython/commit/ffe29dbcd96dc2fbda212f8335908fa1bc8ed893

New changeset b7eb1024d06e51598fc8a19ed6e22b91120c6a1e by Miss Islington (bot) in branch '3.7':
bpo-33763: IDLE: Replace label widget with text widget in code context (GH-7367)
https://github.com/python/cpython/commit/b7eb1024d06e51598fc8a19ed6e22b91120c6a1e

I believe the colorizer would need some new code, maybe in a subclass, but it should be possible.  I would not know if I liked it until we tried it ;-).