Enable doctest running for several other documents.
We have now over 640 doctests that are run with "make doctest".
diff --git a/Doc/library/base64.rst b/Doc/library/base64.rst
index daa8fd5..68a941f 100644
--- a/Doc/library/base64.rst
+++ b/Doc/library/base64.rst
@@ -150,7 +150,7 @@
    :func:`encodestring` returns a string containing one or more lines of
    base64-encoded data always including an extra trailing newline (``'\n'``).
 
-An example usage of the module::
+An example usage of the module:
 
    >>> import base64
    >>> encoded = base64.b64encode('data to be encoded')