Clarify that GzipFile.read1() is now implemented
diff --git a/Doc/library/gzip.rst b/Doc/library/gzip.rst
index a2fa3fa..59ea9d3 100644
--- a/Doc/library/gzip.rst
+++ b/Doc/library/gzip.rst
@@ -94,6 +94,9 @@
    .. versionchanged:: 3.2
       Support for unseekable files was added.
 
+   .. versionchanged:: 3.3
+      The :meth:`io.BufferedIOBase.read1` method is now implemented.
+
 
 .. function:: open(filename, mode='rb', compresslevel=9)