Update

Author: vstinner

peps/pep-0782.rst

@@ -271,7 +271,11 @@ Create the string ``"Hello World"``::
 Reference Implementation
 ========================
 
-* `Pull request gh-131681 <https://github.com/python/cpython/pull/131681>`__.
+`Pull request gh-131681 <https://github.com/python/cpython/pull/131681>`__.
+
+The implementation allocates internally a :class:`bytes` object, so
+:c:func:`PyBytesWriter_Finish` just returns the object without having
+to copy memory.
 
 
 Backwards Compatibility