[3.6] Fix typos in multiple `.rst` files (GH-1668) (#1702)

(cherry picked from commit 3378b2062c7fbb77a9b5e6d315d6b94160fac69a)
diff --git a/Doc/library/email.parser.rst b/Doc/library/email.parser.rst
index c323ebc..dea409d 100644
--- a/Doc/library/email.parser.rst
+++ b/Doc/library/email.parser.rst
@@ -139,7 +139,7 @@
 .. class:: BytesParser(_class=None, *, policy=policy.compat32)
 
    Create a :class:`BytesParser` instance.  The *_class* and *policy*
-   arguments have the same meaning and sematnics as the *_factory*
+   arguments have the same meaning and semantics as the *_factory*
    and *policy* arguments of :class:`BytesFeedParser`.
 
    Note: **The policy keyword should always be specified**; The default will