Remove two lingering references to now-gone has_key() methods from the library docs.
diff --git a/Doc/library/xml.sax.reader.rst b/Doc/library/xml.sax.reader.rst
index c3534bb..bb802ee 100644
--- a/Doc/library/xml.sax.reader.rst
+++ b/Doc/library/xml.sax.reader.rst
@@ -324,8 +324,9 @@
---------------------------------
:class:`Attributes` objects implement a portion of the mapping protocol,
-including the methods :meth:`copy`, :meth:`get`, :meth:`has_key`, :meth:`items`,
-:meth:`keys`, and :meth:`values`. The following methods are also provided:
+including the methods :meth:`copy`, :meth:`get`, :meth:`__contains__`,
+:meth:`items`, :meth:`keys`, and :meth:`values`. The following methods
+are also provided:
.. method:: Attributes.getLength()