fix versionchanged
diff --git a/Doc/library/bz2.rst b/Doc/library/bz2.rst
index 4808b47..ee79edc 100644
--- a/Doc/library/bz2.rst
+++ b/Doc/library/bz2.rst
@@ -60,7 +60,7 @@
 
    :class:`BZ2File` supports the :keyword:`with` statement.
 
-   .. versionchanged:: 2.7
+   .. versionchanged:: 3.1
       Support for the :keyword:`with` statement was added.