Add whatsnew for removal of asyncio.loop.create_datagram_endpoint()'s *reuse_address* parameter (#17595)

diff --git a/Doc/whatsnew/3.6.rst b/Doc/whatsnew/3.6.rst
index 3f5f520..04c1f7e 100644
--- a/Doc/whatsnew/3.6.rst
+++ b/Doc/whatsnew/3.6.rst
@@ -2433,3 +2433,13 @@
 when provided with input that does not have a trailing new line.  This behavior
 now matches what the C tokenizer does internally.
 (Contributed by Ammar Askar in :issue:`33899`.)
+
+Notable changes in Python 3.6.10
+================================
+
+Due to significant security concerns, the *reuse_address* parameter of
+:meth:`asyncio.loop.create_datagram_endpoint` is no longer supported. This is
+because of the behavior of the socket option ``SO_REUSEADDR`` in UDP. For more
+details, see the documentation for ``loop.create_datagram_endpoint()``.
+(Contributed by Kyle Stanley, Antoine Pitrou, and Yury Selivanov in
+:issue:`37228`.)
diff --git a/Doc/whatsnew/3.7.rst b/Doc/whatsnew/3.7.rst
index 2197bd9..8a70fe2 100644
--- a/Doc/whatsnew/3.7.rst
+++ b/Doc/whatsnew/3.7.rst
@@ -2541,3 +2541,13 @@
 to be upgraded or recreated with each Python update. However, note that this
 release will still require recreation of virtual environments in order to get
 the new scripts.
+
+Notable changes in Python 3.7.6
+===============================
+
+Due to significant security concerns, the *reuse_address* parameter of
+:meth:`asyncio.loop.create_datagram_endpoint` is no longer supported. This is
+because of the behavior of the socket option ``SO_REUSEADDR`` in UDP. For more
+details, see the documentation for ``loop.create_datagram_endpoint()``.
+(Contributed by Kyle Stanley, Antoine Pitrou, and Yury Selivanov in
+:issue:`37228`.)
diff --git a/Doc/whatsnew/3.8.rst b/Doc/whatsnew/3.8.rst
index c71c1ab..0927a96 100644
--- a/Doc/whatsnew/3.8.rst
+++ b/Doc/whatsnew/3.8.rst
@@ -2204,3 +2204,13 @@
         loop_overhead                    0.3     0.5     0.6     0.4     0.3     0.3
 
     (Measured from the macOS 64-bit builds found at python.org)
+
+Notable changes in Python 3.8.1
+===============================
+
+Due to significant security concerns, the *reuse_address* parameter of
+:meth:`asyncio.loop.create_datagram_endpoint` is no longer supported. This is
+because of the behavior of the socket option ``SO_REUSEADDR`` in UDP. For more
+details, see the documentation for ``loop.create_datagram_endpoint()``.
+(Contributed by Kyle Stanley, Antoine Pitrou, and Yury Selivanov in
+:issue:`37228`.)
diff --git a/Doc/whatsnew/3.9.rst b/Doc/whatsnew/3.9.rst
index 7cf49bf..64361bb 100644
--- a/Doc/whatsnew/3.9.rst
+++ b/Doc/whatsnew/3.9.rst
@@ -129,6 +129,13 @@
 asyncio
 -------
 
+Due to significant security concerns, the *reuse_address* parameter of
+:meth:`asyncio.loop.create_datagram_endpoint` is no longer supported. This is
+because of the behavior of the socket option ``SO_REUSEADDR`` in UDP. For more
+details, see the documentation for ``loop.create_datagram_endpoint()``.
+(Contributed by Kyle Stanley, Antoine Pitrou, and Yury Selivanov in
+:issue:`37228`.)
+
 Added a new :term:`coroutine` :meth:`~asyncio.loop.shutdown_default_executor`
 that schedules a shutdown for the default executor that waits on the
 :class:`~concurrent.futures.ThreadPoolExecutor` to finish closing. Also,