PEP 767: Annotating Read-Only Attributes (python#4127)

Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Co-authored-by: Carl Meyer <carl@oddbird.net>
Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>

Author: 4 people

.github/CODEOWNERS

@@ -643,6 +643,7 @@ peps/pep-0762.rst  @pablogsal @ambv @lysnikolaou @emilyemorehouse
 peps/pep-0763.rst  @dstufft
 peps/pep-0765.rst  @iritkatriel @ncoghlan
 peps/pep-0766.rst  @warsaw
+peps/pep-0767.rst  @carljm
 # ...
 peps/pep-0777.rst  @warsaw
 # ...