Add first Acknowledgements

Author: Daraan

peps/pep-0821.rst

@@ -326,8 +326,12 @@ Open Questions
 
 Acknowledgements
 ================
-TODO
 
+Thanks to Jelle Zijlstra for sponsoring this PEP.
+
+Hugo van Kemenade, for helpful feedback on the draft and PR of this PEP.
+
+Eric Traut, for feedback on the initial idea and discussions.
 
 
 References