As of Python 3.3 it is possible again to prefix unicode strings with a
``u`` prefix to simplify maintenance of dual 2.x and 3.x codebases.
-Bytes literals may optionally be prefixed with a letter ``'r'``
+Both string and bytes literals may optionally be prefixed with a letter ``'r'``
or ``'R'``; such strings are called :dfn:`raw strings` and treat backslashes as
literal characters. As a result, in string literals, ``'\U'`` and ``'\u'``
escapes in raw strings are not treated specially. Given that Python 2.x's raw