Partial py3k-ification of Doc/library/: convert has_key references into either 'k in d' or __contains__; normalize raise statements; convert print statements into print function calls.
diff --git a/Doc/library/rfc822.rst b/Doc/library/rfc822.rst
index da9f536..bd8c9a2 100644
--- a/Doc/library/rfc822.rst
+++ b/Doc/library/rfc822.rst
@@ -260,7 +260,7 @@
:class:`Message` instances also support a limited mapping interface. In
particular: ``m[name]`` is like ``m.getheader(name)`` but raises :exc:`KeyError`
if there is no matching header; and ``len(m)``, ``m.get(name[, default])``,
-``m.has_key(name)``, ``m.keys()``, ``m.values()`` ``m.items()``, and
+``m.__contains__(name)``, ``m.keys()``, ``m.values()`` ``m.items()``, and
``m.setdefault(name[, default])`` act as expected, with the one difference
that :meth:`setdefault` uses an empty string as the default value.
:class:`Message` instances also support the mapping writable interface ``m[name]