Sentence cased True and False to be more pythonic

[Nujra40]

[ghost]

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[ziima]

It seems to me that in all these cases, "true" or "false" do not refer to Python entities, but are used as part of natural language.

I suggest to reject this PR.

[rhettinger]

We use lower true to mean any value such that bool(value) returns True.

We use uppercase True for the actual true singleton.