Remove many "versionchanged" items that didn't use the official markup,
but just some text embedded in the docs.
Also remove paragraph about implicit relative imports from tutorial.
diff --git a/Doc/library/shlex.rst b/Doc/library/shlex.rst
index 4c509d8..7d88610 100644
--- a/Doc/library/shlex.rst
+++ b/Doc/library/shlex.rst
@@ -43,15 +43,14 @@
A :class:`shlex` instance or subclass instance is a lexical analyzer object.
The initialization argument, if present, specifies where to read characters
from. It must be a file-/stream-like object with :meth:`read` and
- :meth:`readline` methods, or a string (strings are accepted since Python 2.3).
- If no argument is given, input will be taken from ``sys.stdin``. The second
- optional argument is a filename string, which sets the initial value of the
- :attr:`infile` member. If the *instream* argument is omitted or equal to
- ``sys.stdin``, this second argument defaults to "stdin". The *posix* argument
- was introduced in Python 2.3, and defines the operational mode. When *posix* is
- not true (default), the :class:`shlex` instance will operate in compatibility
- mode. When operating in POSIX mode, :class:`shlex` will try to be as close as
- possible to the POSIX shell parsing rules.
+ :meth:`readline` methods, or a string. If no argument is given, input will
+ be taken from ``sys.stdin``. The second optional argument is a filename
+ string, which sets the initial value of the :attr:`infile` member. If the
+ *instream* argument is omitted or equal to ``sys.stdin``, this second
+ argument defaults to "stdin". The *posix* argument defines the operational
+ mode: when *posix* is not true (default), the :class:`shlex` instance will
+ operate in compatibility mode. When operating in POSIX mode, :class:`shlex`
+ will try to be as close as possible to the POSIX shell parsing rules.
.. seealso::