PEP 747: Link to mypy reference implementation (#4700)

Author: davidfstr

peps/pep-0747.rst

@@ -516,12 +516,14 @@ Reference Implementation
 
 Pyright (version 1.1.379) provides a reference implementation for ``TypeForm``.
 
-Mypy contributors also `plan to implement <https://github.com/python/mypy/issues/9773>`__
-support for ``TypeForm``.
+Mypy (`commit 1b7e71`_; Nov 3, 2025) provides
+a reference implementation for ``TypeForm``.
 
 A reference implementation of the runtime component is provided in the
 ``typing_extensions`` module.
 
+.. _commit 1b7e71: https://github.com/python/mypy/commit/1b7e717ecc56cd13d76bc110a1db2796e8b3c918
+
 
 Rejected Ideas
 ==============