2.7 -> 3.1 versionchanges.
diff --git a/Doc/library/hashlib.rst b/Doc/library/hashlib.rst
index 36f386c..69facce 100644
--- a/Doc/library/hashlib.rst
+++ b/Doc/library/hashlib.rst
@@ -105,7 +105,7 @@
    concatenation of all the arguments: ``m.update(a); m.update(b)`` is
    equivalent to ``m.update(a+b)``.
 
-   .. versionchanged:: 2.7
+   .. versionchanged:: 3.1
 
       The Python GIL is released to allow other threads to run while
       hash updates on data larger than 2048 bytes is taking place when