diff --git a/Doc/library/signal.rst b/Doc/library/signal.rst
index 84e2836..a97ce66 100644
--- a/Doc/library/signal.rst
+++ b/Doc/library/signal.rst
@@ -65,6 +65,16 @@
 Module contents
 ---------------
 
+.. versionchanged:: 3.5
+   signal (SIG*), handler (:const:`SIG_DFL`, :const:`SIG_IGN`) and sigmask
+   (:const:`SIG_BLOCK`, :const:`SIG_UNBLOCK`, :const:`SIG_SETMASK`)
+   related constants listed below were turned into
+   :class:`enums <enum.IntEnum>`.
+   :func:`getsignal`, :func:`pthread_sigmask`, :func:`sigpending` and
+   :func:`sigwait` functions return human-readable
+   :class:`enums <enum.IntEnum>`.
+
+
 The variables defined in the :mod:`signal` module are:
 
 
diff --git a/Doc/whatsnew/3.5.rst b/Doc/whatsnew/3.5.rst
index 78bddcb..4218134 100644
--- a/Doc/whatsnew/3.5.rst
+++ b/Doc/whatsnew/3.5.rst
@@ -134,6 +134,11 @@
 Improved Modules
 ================
 
+* Different constants of :mod:`signal` module are now enumeration values using
+  the :mod:`enum` module. This allows meaningful names to be printed during
+  debugging, instead of integer “magic numbers”. (contribute by Giampaolo
+  Rodola' in :issue:`21076`)
+
 * :class:`xmlrpc.client.ServerProxy` is now a :term:`context manager`
   (contributed by Claudiu Popa in :issue:`20627`).